$CHRD
Chord Energy Corp Stock $chrd

$chrd Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000148615920000018 Filed on February 27, 2020

Income Statement

Concept	2019 Q4	2018 Q4	2018 Q3
Revenue	$483.9M	$599.8M	$674.6M
YoY Change	-19.32%	48.28%	121.37%
Cost Of Revenue	$178.0M	$535.9M	$281.6M
YoY Change	-66.78%	213.76%	177.44%
Gross Profit	$305.9M	$317.1M	$393.0M
YoY Change	-3.53%	13.7%	93.41%
Gross Profit Margin	63.22%	52.87%	58.25%
Selling, General & Admin	$58.00M	$63.00M	$65.60M
YoY Change	-7.94%	59.09%	74.47%
% of Gross Profit	18.96%	19.87%	16.69%
Research & Development	$4.300M	$3.700M	$22.30M
YoY Change	16.22%	-51.32%	2377.78%
% of Gross Profit	1.41%	1.17%	5.67%
Depreciation & Amortization	$209.2M	$170.5M	$163.0M
YoY Change	22.7%	16.3%	23.2%
% of Gross Profit	68.39%	53.77%	41.47%
Operating Expenses	$271.4M	$237.1M	$250.8M
YoY Change	14.47%	22.34%	46.84%
Operating Profit	$23.97M	$69.66M	$179.0M
YoY Change	-65.59%	-19.1%	452.71%
Interest Expense	-$116.0M	$226.9M	$39.56M
YoY Change	-151.12%	-241.64%	5.81%
% of Operating Profit	-484.02%	325.74%	22.1%
Other Income/Expense, Net	-$300.0K	$0.00	-$88.04M
YoY Change		-100.0%	-4.62%
Pretax Income	-$88.00M	$296.4M	$91.01M
YoY Change	-129.69%	-496.79%	-251.9%
Income Tax	-$23.90M	$69.50M	$24.78M
% Of Pretax Income		23.45%	27.23%
Net Earnings	-$76.41M	$222.0M	$62.34M
YoY Change	-134.42%	78.13%	-251.26%
Net Earnings / Revenue	-15.79%	37.01%	9.24%
Basic Earnings Per Share	-$0.24	$0.71	$0.20
Diluted Earnings Per Share	-$0.24	$0.70	$0.20
COMMON SHARES
Basic Shares Outstanding	321.3M shares	318.4M shares	313.2M shares
Diluted Shares Outstanding			316.4M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$20.00M	$22.20M	$16.90M
YoY Change	-9.91%	32.93%	98.82%
Cash & Equivalents	$20.02M	$22.19M	$16.89M
Short-Term Investments
Other Short-Term Assets	$346.0K	$183.0K	$192.0K
YoY Change	89.07%	-5.18%	195.38%
Inventory	$35.26M	$33.13M	$31.41M
Prepaid Expenses	$10.01M	$11.00M	$6.444M
Receivables	$371.2M	$387.6M	$428.2M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$437.4M	$554.2M	$483.5M
YoY Change	-21.08%	33.33%	49.95%
LONG-TERM ASSETS
Property, Plant & Equipment	$6.978B	$7.027B	$6.900B
YoY Change	-0.7%	13.83%	14.32%
Goodwill	$0.00
YoY Change
Intangibles	$0.00	$125.0K
YoY Change	-100.0%
Long-Term Investments
YoY Change
Other Assets	$29.44M	$25.67M	$20.19M
YoY Change	14.67%	18.86%	-6.37%
Total Long-Term Assets	$7.062B	$7.072B	$6.933B
YoY Change	-0.14%	13.93%	14.24%
TOTAL ASSETS
Total Short-Term Assets	$437.4M	$554.2M	$483.5M
Total Long-Term Assets	$7.062B	$7.072B	$6.933B
Total Assets	$7.499B	$7.626B	$7.416B
YoY Change	-1.66%	15.15%	16.04%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$17.95M	$20.17M	$17.21M
YoY Change	-11.0%	50.83%	5.25%
Accrued Expenses	$281.1M	$331.7M	$307.5M
YoY Change	-15.25%	35.77%	58.39%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$0.00
YoY Change
Total Short-Term Liabilities	$602.9M	$611.8M	$816.7M
YoY Change	-1.45%	-3.09%	93.67%
LONG-TERM LIABILITIES
Long-Term Debt	$2.712B	$2.735B	$2.633B
YoY Change	-0.87%	30.4%	12.49%
Other Long-Term Liabilities	$6.019M	$7.751M	$7.775M
YoY Change	-22.35%	25.38%	33.94%
Total Long-Term Liabilities	$2.718B	$2.743B	$2.641B
YoY Change	-0.93%	30.39%	12.55%
TOTAL LIABILITIES
Total Short-Term Liabilities	$602.9M	$611.8M	$816.7M
Total Long-Term Liabilities	$2.718B	$2.743B	$2.641B
Total Liabilities	$3.662B	$3.707B	$3.772B
YoY Change	-1.22%	19.23%	13.2%
SHAREHOLDERS EQUITY
Retained Earnings	$554.4M	$682.7M	$460.7M
YoY Change	-18.78%	-4.92%	-22.36%
Common Stock	$3.116B	$3.081B	$3.074B
YoY Change	1.13%	14.96%	29.62%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$33.88M	$29.03M	$28.99M
YoY Change	16.73%	30.87%	30.96%
Treasury Stock Shares	2.967M shares	2.092M shares	2.089M shares
Shareholders Equity	$3.636B	$3.735B	$3.506B
YoY Change
Total Liabilities & Shareholders Equity	$7.499B	$7.626B	$7.416B
YoY Change	-1.66%	15.15%	16.04%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018 Q3
OPERATING ACTIVITIES
Net Income	-$76.41M	$222.0M	$62.34M
YoY Change	-134.42%	78.13%	-251.26%
Depreciation, Depletion And Amortization	$209.2M	$170.5M	$163.0M
YoY Change	22.7%	16.3%	23.2%
Cash From Operating Activities	$253.0M	$234.4M	$230.0M
YoY Change	7.94%	12.05%	159.01%
INVESTING ACTIVITIES
Capital Expenditures	$167.6M	$309.6M	$359.8M
YoY Change	-45.87%	16.57%	88.28%
Acquisitions
YoY Change
Other Investing Activities	$9.700M	-$50.20M	$262.8M
YoY Change	-119.32%	709.68%	3451.35%
Cash From Investing Activities	-$158.0M	-$359.8M	-$97.00M
YoY Change	-56.09%	32.38%	-47.25%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-94.50M	130.7M	-133.2M
YoY Change	-172.3%	84.34%	-244.78%
NET CHANGE
Cash From Operating Activities	253.0M	234.4M	230.0M
Cash From Investing Activities	-158.0M	-359.8M	-97.00M
Cash From Financing Activities	-94.50M	130.7M	-133.2M
Net Change In Cash	500.0K	5.300M	-200.0K
YoY Change	-90.57%	-36.14%	-93.55%
FREE CASH FLOW
Cash From Operating Activities	$253.0M	$234.4M	$230.0M
Capital Expenditures	$167.6M	$309.6M	$359.8M
Free Cash Flow	$85.40M	-$75.20M	-$129.8M
YoY Change	-213.56%	33.33%	26.88%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2019	dei	Amendment Flag AmendmentFlag	false
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0001486159
CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
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CY2019Q2	dei	Entity Public Float EntityPublicFloat	1791664921	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
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CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Type DocumentType	10-K
CY2019	dei	Document Annual Report DocumentAnnualReport	true
CY2019	dei	Document Period End Date DocumentPeriodEndDate	2019-12-31
CY2019	dei	Document Transition Report DocumentTransitionReport	false
CY2019	dei	Entity File Number EntityFileNumber	1-34776
CY2019	dei	Entity Registrant Name EntityRegistrantName	Oasis Petroleum Inc.
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	80-0554627
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	1001 Fannin Street
CY2019	dei	Entity Address Address Line2 EntityAddressAddressLine2	Suite 1500
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	Houston
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	TX
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	77002
CY2019	dei	City Area Code CityAreaCode	281
CY2019	dei	Local Phone Number LocalPhoneNumber	404-9500
CY2019	dei	Security12b Title Security12bTitle	Common Stock
CY2019	dei	Trading Symbol TradingSymbol	OAS
CY2019	dei	Security Exchange Name SecurityExchangeName	NASDAQ
CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2019	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2019	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2019	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2019	dei	Entity Small Business EntitySmallBusiness	false
CY2019	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019	dei	Entity Shell Company EntityShellCompany	false
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CY2018Q4	us-gaap	Inventory Net InventoryNet	33128000	USD
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CY2018Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	99930000	USD
CY2019Q4	us-gaap	Intangible Assets Current IntangibleAssetsCurrent	0	USD
CY2018Q4	us-gaap	Intangible Assets Current IntangibleAssetsCurrent	125000	USD
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CY2019Q4	us-gaap	Oil And Gas Property Successful Effort Method Gross OilAndGasPropertySuccessfulEffortMethodGross	9463038000	USD
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CY2018	us-gaap	Interest Expense InterestExpense	159085000	USD
CY2017	us-gaap	Interest Expense InterestExpense	146837000	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-13848000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	37596000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	15796000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3650000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-128243000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-35296000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	123796000	USD
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.41
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	440000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	121000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1332000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-277785000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-144355000	USD
CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-219826000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-123362000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-25343000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-75858000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-32715000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5843000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-203304000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	-90647000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	-19500000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	127446000	USD
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.11
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.53
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.41
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.11
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.52
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	315002000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	307480000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	234986000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	315002000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	307480000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	237875000	shares
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2923157000	USD
CY2017Q1	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	4724000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	55000	USD
CY2017	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	302191000	USD
CY2017	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	28160000	USD
CY2017	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	134185000	USD
CY2017	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	6229000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	127446000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3513579000	USD
CY2018	us-gaap	Stock Issued During Period Value Acquisitions StockIssuedDuringPeriodValueAcquisitions	371220000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	31044000	USD
CY2018	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	44503000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	14114000	USD
CY2018	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	6846000	USD
CY2018	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	-1006000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	-19500000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3918880000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	35392000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	21270000	USD
CY2019	us-gaap	Adjustments Related To Tax Withholding For Share Based Compensation AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation	4856000	USD
CY2019	us-gaap	Stock Issued During Period Value Other StockIssuedDuringPeriodValueOther	-418000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	-90647000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3837081000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	-90647000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	-19500000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	127446000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	787192000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	636296000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	530802000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4312000	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-13848000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	USD
CY2019	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	-4455000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	28587000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	1774000	USD
CY2019	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	10257000	USD
CY2018	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	384228000	USD
CY2017	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	6887000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-32699000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5866000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-202884000	USD
CY2019	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-106314000	USD
CY2018	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	28457000	USD
CY2017	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-71657000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	33607000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	29273000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	26534000	USD
CY2019	oas	Debt Discount Amortization And Other DebtDiscountAmortizationAndOther	27263000	USD
CY2018	oas	Debt Discount Amortization And Other DebtDiscountAmortizationAndOther	29057000	USD
CY2017	oas	Debt Discount Amortization And Other DebtDiscountAmortizationAndOther	18311000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-13729000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	23508000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	166386000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	5893000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	14346000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	2501000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-325000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	2354000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	838000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	53051000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	26116000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	123107000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	9789000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-221000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	22485000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	892853000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	996421000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	507876000	USD
CY2019	us-gaap	Payments To Explore And Develop Oil And Gas Properties PaymentsToExploreAndDevelopOilAndGasProperties	869221000	USD
CY2018	us-gaap	Payments To Explore And Develop Oil And Gas Properties PaymentsToExploreAndDevelopOilAndGasProperties	1148961000	USD
CY2017	us-gaap	Payments To Explore And Develop Oil And Gas Properties PaymentsToExploreAndDevelopOilAndGasProperties	647349000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	21009000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	581650000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	61874000	USD
CY2019	us-gaap	Proceeds From Sale Of Oil And Gas Property And Equipment ProceedsFromSaleOfOilAndGasPropertyAndEquipment	42376000	USD
CY2017	us-gaap	Proceeds From Sale Of Oil And Gas Property And Equipment ProceedsFromSaleOfOilAndGasPropertyAndEquipment	5774000	USD
CY2018	us-gaap	Proceeds From Sale Of Oil And Gas Property And Equipment ProceedsFromSaleOfOilAndGasPropertyAndEquipment	333229000	USD
CY2019	oas	Paymentsfor Costs Relatedto Divestitureof Businesses PaymentsforCostsRelatedtoDivestitureofBusinesses	0	USD
CY2018	oas	Paymentsfor Costs Relatedto Divestitureof Businesses PaymentsforCostsRelatedtoDivestitureofBusinesses	2850000	USD
CY2017	oas	Paymentsfor Costs Relatedto Divestitureof Businesses PaymentsforCostsRelatedtoDivestitureofBusinesses	366000	USD
CY2019	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	-19098000	USD
CY2018	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	213528000	USD
CY2017	us-gaap	Payments For Proceeds From Derivative Instrument Investing Activities PaymentsForProceedsFromDerivativeInstrumentInvestingActivities	8264000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-224000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	2681000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-828756000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1613536000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-714760000	USD
CY2019	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	1982000000	USD
CY2018	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	3224000000	USD
CY2017	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	1162000000	USD
CY2019	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	1972500000	USD
CY2018	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	2586000000	USD
CY2017	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	1377000000	USD
CY2019	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	45790000	USD
CY2018	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	423340000	USD
CY2017	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	0	USD
CY2019	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	400000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	0	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1052000	USD
CY2018	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	13862000	USD
CY2017	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	2714000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	0	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	302191000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Limited Partners Units ProceedsFromIssuanceOfCommonLimitedPartnersUnits	0	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5470000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Limited Partners Units ProceedsFromIssuanceOfCommonLimitedPartnersUnits	44503000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Limited Partners Units ProceedsFromIssuanceOfCommonLimitedPartnersUnits	134185000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	4856000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6846000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6229000	USD
CY2019	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	21270000	USD
CY2018	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	14114000	USD
CY2017	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	0	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2382000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-418000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1756000	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-55000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-66268000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	622585000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	212378000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2171000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5494000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	22190000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	16720000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	11226000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	20019000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	22190000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	16720000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	155833000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	141196000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	129463000	USD
CY2019	us-gaap	Income Taxes Paid IncomeTaxesPaid	111000	USD
CY2018	us-gaap	Income Taxes Paid IncomeTaxesPaid	38000	USD
CY2017	us-gaap	Income Taxes Paid IncomeTaxesPaid	12000	USD
CY2019	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	146000	USD
CY2018	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	25000	USD
CY2017	us-gaap	Proceeds From Income Tax Refunds ProceedsFromIncomeTaxRefunds	281000	USD
CY2019	oas	Change In Capital Expenditures Incurred But Not Yet Paid ChangeInCapitalExpendituresIncurredButNotYetPaid	-82414000	USD
CY2018	oas	Change In Capital Expenditures Incurred But Not Yet Paid ChangeInCapitalExpendituresIncurredButNotYetPaid	68946000	USD
CY2017	oas	Change In Capital Expenditures Incurred But Not Yet Paid ChangeInCapitalExpendituresIncurredButNotYetPaid	83508000	USD
CY2019	oas	Non Cash Asset Retirement Obligations NonCashAssetRetirementObligations	4917000	USD
CY2018	oas	Non Cash Asset Retirement Obligations NonCashAssetRetirementObligations	3880000	USD
CY2017	oas	Non Cash Asset Retirement Obligations NonCashAssetRetirementObligations	-789000	USD
CY2019	us-gaap	Noncash Or Part Noncash Acquisition Debt Assumed1 NoncashOrPartNoncashAcquisitionDebtAssumed1	0	USD
CY2018	us-gaap	Noncash Or Part Noncash Acquisition Debt Assumed1 NoncashOrPartNoncashAcquisitionDebtAssumed1	0	USD
CY2017	us-gaap	Noncash Or Part Noncash Acquisition Debt Assumed1 NoncashOrPartNoncashAcquisitionDebtAssumed1	4875000	USD
CY2019	us-gaap	Business Combination Consideration Transferred Equity Interests Issued And Issuable BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable	0	USD
CY2018	us-gaap	Business Combination Consideration Transferred Equity Interests Issued And Issuable BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable	371220000	USD
CY2017	us-gaap	Business Combination Consideration Transferred Equity Interests Issued And Issuable BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable	0	USD
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-top:10pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%;">Use of Estimates</span></div><div style="margin-top:5pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">Preparation of the Company’s consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. The most significant estimates pertain to proved crude oil and natural gas reserves and related cash flow estimates used in impairment tests of long-lived assets, estimates of future development, dismantlement and abandonment costs, estimates relating to certain crude oil and natural gas revenues and expenses and estimates of expenses related to legal, environmental and other contingencies. Certain of these estimates require assumptions regarding future commodity prices, future costs and expenses and future production rates. Actual results could differ from those estimates.</span></div><div style="margin-top:5pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">Estimates of crude oil and natural gas reserves and their values, future production rates and future costs and expenses are inherently uncertain for numerous reasons, including many factors beyond the Company’s control. Reservoir engineering is a subjective process of estimating underground accumulations of crude oil and natural gas that cannot be measured in an exact manner. The accuracy of any reserve estimate is a function of the quality of data available and of engineering and geological interpretation and judgment. In addition, estimates of reserves may be revised based on actual production, results of subsequent exploration and development activities, prevailing commodity prices, operating costs and other factors. These revisions may be material and could materially affect future depreciation, depletion and amortization (“DD&A”) expense, dismantlement and abandonment costs, and impairment expense.</span></div>
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1300000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1500000	USD
CY2019	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	12000000.0	USD
CY2018	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	17200000	USD
CY2017	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	12800000	USD
CY2018Q4	us-gaap	Capitalized Exploratory Well Costs CapitalizedExploratoryWellCosts	4457000	USD
CY2017Q4	us-gaap	Capitalized Exploratory Well Costs CapitalizedExploratoryWellCosts	0	USD
CY2016Q4	us-gaap	Capitalized Exploratory Well Costs CapitalizedExploratoryWellCosts	2097000	USD
CY2019	us-gaap	Capitalized Exploratory Well Cost Additions Pending Determination Of Proved Reserves CapitalizedExploratoryWellCostAdditionsPendingDeterminationOfProvedReserves	0	USD
CY2018	us-gaap	Capitalized Exploratory Well Cost Additions Pending Determination Of Proved Reserves CapitalizedExploratoryWellCostAdditionsPendingDeterminationOfProvedReserves	26497000	USD
CY2017	us-gaap	Capitalized Exploratory Well Cost Additions Pending Determination Of Proved Reserves CapitalizedExploratoryWellCostAdditionsPendingDeterminationOfProvedReserves	10000	USD
CY2019	us-gaap	Reclassification To Well Facilities And Equipment Based On Determination Of Proved Reserves ReclassificationToWellFacilitiesAndEquipmentBasedOnDeterminationOfProvedReserves	4222000	USD
CY2018	us-gaap	Reclassification To Well Facilities And Equipment Based On Determination Of Proved Reserves ReclassificationToWellFacilitiesAndEquipmentBasedOnDeterminationOfProvedReserves	22040000	USD
CY2017	us-gaap	Reclassification To Well Facilities And Equipment Based On Determination Of Proved Reserves ReclassificationToWellFacilitiesAndEquipmentBasedOnDeterminationOfProvedReserves	571000	USD
CY2019	us-gaap	Results Of Operations Dry Hole Costs ResultsOfOperationsDryHoleCosts	235000	USD
CY2018	us-gaap	Results Of Operations Dry Hole Costs ResultsOfOperationsDryHoleCosts	0	USD
CY2017	us-gaap	Results Of Operations Dry Hole Costs ResultsOfOperationsDryHoleCosts	1536000	USD
CY2019Q4	us-gaap	Capitalized Exploratory Well Costs CapitalizedExploratoryWellCosts	0	USD
CY2018Q4	us-gaap	Capitalized Exploratory Well Costs CapitalizedExploratoryWellCosts	4457000	USD
CY2017Q4	us-gaap	Capitalized Exploratory Well Costs CapitalizedExploratoryWellCosts	0	USD
CY2019Q4	us-gaap	Capitalized Exploratory Well Costs That Have Been Capitalized For Period Greater Than One Year CapitalizedExploratoryWellCostsThatHaveBeenCapitalizedForPeriodGreaterThanOneYear	0	USD
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="margin-top:10pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%;">Concentrations of Market and Credit Risk</span></div><div style="margin-top:5pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">The future results of the Company’s crude oil and natural gas operations will be affected by the market prices of crude oil and natural gas. The availability of a ready market for crude oil and natural gas products in the future will depend on numerous factors beyond the control of the Company, including weather, imports, marketing of competitive fuels, proximity and capacity of crude oil and natural gas pipelines and other transportation facilities, any oversupply or undersupply of crude oil, natural gas and liquid products, the regulatory environment, the economic environment, and other regional and political events, none of which can be predicted with certainty. The current global oversupply of crude oil has caused a sharp decline in crude oil prices since mid-2014, though recently crude oil prices have been improving. A substantial or extended decline in the price of crude oil could have a material adverse effect on the Company’s financial position, cash flows and results of operations.</span></div><div style="margin-top:5pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">The Company operates in the exploration, development and production sector of the crude oil and gas industry. The Company’s receivables include amounts due from purchasers of its crude oil and natural gas production and amounts due from joint interest partners for their respective portions of operating expenses and exploration and development costs. While certain of these customers and joint interest partners are affected by periodic downturns in the economy in general or in their specific segment of the crude oil or natural gas industry, including the current period of low commodity prices, the Company believes that its level of credit-related losses due to such economic fluctuations has been and will continue to be immaterial to the Company’s results of operations over the long-term. In addition, a portion of the Company’s trade receivables are collateralized.</span></div><div style="margin-top:5pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">The Company manages and controls market and counterparty credit risk. In the normal course of business, collateral is not required for financial instruments with credit risk. Financial instruments which potentially subject the Company to credit risk consist principally of temporary cash balances and derivative financial instruments. The Company maintains cash and cash equivalents in bank deposit accounts which, at times, may exceed the federally insured limits. The Company has not experienced any significant losses from such investments. The Company attempts to limit the amount of credit exposure to any one financial institution or company. The Company believes the credit quality of its customers is generally high. In the normal course of business, letters of credit or parent guarantees are required for counterparties which management perceives to have a higher credit risk.</span></div>
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2019Q4	oas	Derivative Numberof Counterparties DerivativeNumberofCounterparties	9	counterparty
CY2019Q4	oas	Derivative Instrument Receivables From Counterparty Past Due DerivativeInstrumentReceivablesFromCounterpartyPastDue	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2018Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	0	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	0	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	0	USD
CY2018Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	0	USD
CY2019	oas	Contract With Customer Liability Cash Received ContractWithCustomerLiabilityCashReceived	2174000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	69000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	2105000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	18452000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	20203000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	19244000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	12642000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	11870000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	2768000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	85179000	USD
CY2019	us-gaap	Revenue Performance Obligation Description Of Timing RevenuePerformanceObligationDescriptionOfTiming	The partially and wholly unsatisfied performance obligations presented in the table above are generally limited to customer contracts which have fixed pricing and fixed volume terms and conditions, which generally include customer contracts with minimum volume commitment payment obligations.
CY2019Q4	us-gaap	Energy Related Inventory Petroleum EnergyRelatedInventoryPetroleum	18296000	USD
CY2018Q4	us-gaap	Energy Related Inventory Petroleum EnergyRelatedInventoryPetroleum	14933000	USD
CY2019Q4	us-gaap	Other Inventory Supplies OtherInventorySupplies	16963000	USD
CY2018Q4	us-gaap	Other Inventory Supplies OtherInventorySupplies	18195000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	35259000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	33128000	USD
CY2019Q4	oas	Inventory Noncurrent Linefill InventoryNoncurrentLinefill	13924000	USD
CY2018Q4	oas	Inventory Noncurrent Linefill InventoryNoncurrentLinefill	12260000	USD
CY2019Q4	us-gaap	Inventory Noncurrent InventoryNoncurrent	13924000	USD
CY2018Q4	us-gaap	Inventory Noncurrent InventoryNoncurrent	12260000	USD
CY2019Q4	oas	Inventory Currentand Noncurrent InventoryCurrentandNoncurrent	49183000	USD
CY2018Q4	oas	Inventory Currentand Noncurrent InventoryCurrentandNoncurrent	45388000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	372440000	USD
CY2018Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	389128000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1259000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1526000	USD
CY2019Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	371181000	USD
CY2018Q4	us-gaap	Receivables Net Current ReceivablesNetCurrent	387602000	USD
CY2019Q4	oas	Revenue Suspense RevenueSuspense	78950000	USD
CY2018Q4	oas	Revenue Suspense RevenueSuspense	75685000	USD
CY2019Q4	us-gaap	Accrued Royalties Current AccruedRoyaltiesCurrent	133092000	USD
CY2018Q4	us-gaap	Accrued Royalties Current AccruedRoyaltiesCurrent	124884000	USD
CY2019Q4	oas	Production Taxes Payable ProductionTaxesPayable	21048000	USD
CY2018Q4	oas	Production Taxes Payable ProductionTaxesPayable	16126000	USD
CY2019Q4	oas	Revenues Payable And Production Taxes Current RevenuesPayableAndProductionTaxesCurrent	233090000	USD
CY2018Q4	oas	Revenues Payable And Production Taxes Current RevenuesPayableAndProductionTaxesCurrent	216695000	USD
CY2019Q4	oas	Accrued Capital Costs AccruedCapitalCosts	128592000	USD
CY2018Q4	oas	Accrued Capital Costs AccruedCapitalCosts	216079000	USD
CY2019Q4	oas	Accrued Lease Operating Expense AccruedLeaseOperatingExpense	34151000	USD
CY2018Q4	oas	Accrued Lease Operating Expense AccruedLeaseOperatingExpense	26988000	USD
CY2019Q4	oas	Accrued Bulk Purchases AccruedBulkPurchases	51087000	USD
CY2018Q4	oas	Accrued Bulk Purchases AccruedBulkPurchases	32713000	USD
CY2019Q4	oas	Accrued General And Administrative Expense AccruedGeneralAndAdministrativeExpense	41843000	USD
CY2018Q4	oas	Accrued General And Administrative Expense AccruedGeneralAndAdministrativeExpense	23901000	USD
CY2019Q4	oas	Accrued Well Servicesand Midstream Operating Expense AccruedWellServicesandMidstreamOperatingExpense	17958000	USD
CY2018Q4	oas	Accrued Well Servicesand Midstream Operating Expense AccruedWellServicesandMidstreamOperatingExpense	17521000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	7448000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	14449000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	281079000	USD
CY2018Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	331651000	USD
CY2019Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	500000	USD
CY2018Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Assets DerivativeCreditRiskValuationAdjustmentDerivativeAssets	200000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Net DerivativeFairValueOfDerivativeNet	-18641000	USD
CY2019	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-106314000	USD
CY2018	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	28457000	USD
CY2017	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-71657000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	3928000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	2754000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	1174000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	34498000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	14683000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	19815000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	118980000	USD
CY2018Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	12105000	USD
CY2018Q4	us-gaap	Derivative Assets DerivativeAssets	106875000	USD
CY2018Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	104000	USD
CY2018Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	0	USD
CY2018Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	104000	USD
CY2019Q4	us-gaap	Proved Oil And Gas Property Successful Effort Method ProvedOilAndGasPropertySuccessfulEffortMethod	8724376000	USD
CY2018Q4	us-gaap	Proved Oil And Gas Property Successful Effort Method ProvedOilAndGasPropertySuccessfulEffortMethod	7878104000	USD
CY2019Q4	us-gaap	Oil And Gas Property Successful Effort Method Accumulated Depreciation Depletion And Amortization OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAndAmortization	3601019000	USD
CY2018Q4	us-gaap	Oil And Gas Property Successful Effort Method Accumulated Depreciation Depletion And Amortization OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAndAmortization	2853353000	USD
CY2019Q4	oas	Proved Oil And Gas Properties Net ProvedOilAndGasPropertiesNet	5123357000	USD
CY2018Q4	oas	Proved Oil And Gas Properties Net ProvedOilAndGasPropertiesNet	5024751000	USD
CY2019Q4	us-gaap	Unproved Oil And Gas Property Successful Effort Method UnprovedOilAndGasPropertySuccessfulEffortMethod	738662000	USD
CY2018Q4	us-gaap	Unproved Oil And Gas Property Successful Effort Method UnprovedOilAndGasPropertySuccessfulEffortMethod	1034085000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	1279653000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	1151772000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Other Accumulated Depreciation PropertyPlantAndEquipmentOtherAccumulatedDepreciation	163896000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Other Accumulated Depreciation PropertyPlantAndEquipmentOtherAccumulatedDepreciation	183499000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Other Net PropertyPlantAndEquipmentOtherNet	1115757000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Other Net PropertyPlantAndEquipmentOtherNet	968273000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6977776000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	7027109000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	2711573000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	2735276000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	2711600000	USD
CY2019Q4	oas	Collateralized Longterm Debt Percentof Reserve Valueof Oiland Natural Gas Properties CollateralizedLongtermDebtPercentofReserveValueofOilandNaturalGasProperties	0.90
CY2019Q4	oas	Debt Instrument Convertible Debt Number Of Contingent Conversion Conditions Met DebtInstrumentConvertibleDebtNumberOfContingentConversionConditionsMet	0	conversionCondition
CY2019Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	22900000	USD
CY2019	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	7300000	USD
CY2018	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	7600000	USD
CY2017	us-gaap	Amortization Of Financing Costs AmortizationOfFinancingCosts	7000000.0	USD
CY2019	us-gaap	Write Off Of Deferred Debt Issuance Cost WriteOffOfDeferredDebtIssuanceCost	500000	USD
CY2018	us-gaap	Write Off Of Deferred Debt Issuance Cost WriteOffOfDeferredDebtIssuanceCost	4000000.0	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	52449000	USD
CY2017Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	48799000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	1519000	USD
CY2018	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	5854000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	770000	USD
CY2018	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	4944000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	2939000	USD
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	2657000	USD
CY2019	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	647000	USD
CY2018	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	83000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	56784000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	52449000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	500000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	100000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-43000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-70000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-199370000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-4551000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-420000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	27000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	93000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-16000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	23000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-420000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-28148000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-3553000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-2313000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-3514000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-32699000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5866000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-202884000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-32715000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5843000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-203304000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-25906000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.2100
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-5322000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.3500
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-26550000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0290
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-3573000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0208
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-527000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.0259
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	-1966000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	-0.0640
CY2019	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	7895000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	-0.1309
CY2018	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	3317000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	-0.0168
CY2017	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	1278000	USD
CY2019	oas	Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation Percent EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationPercent	-0.0170
CY2019	oas	Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationAmount	2094000	USD
CY2018	oas	Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation Percent EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationPercent	-0.0950
CY2018	oas	Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationAmount	2408000	USD
CY2017	oas	Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation Percent EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationPercent	0.0105
CY2017	oas	Effective Income Tax Rate Reconciliation Nondeductible Expense Executive Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationAmount	-792000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.0175
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	2163000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.0368
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	932000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	0.0087
CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense Share Based Compensation Cost IncomeTaxReconciliationNondeductibleExpenseShareBasedCompensationCost	-659000	USD
CY2017	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	-171900000	USD
CY2019	oas	Effective Income Tax Rate Reconciliation Changein State Deferred Tax Rate Percent EffectiveIncomeTaxRateReconciliationChangeinStateDeferredTaxRatePercent	0
CY2019	oas	Effective Income Tax Rate Reconciliation Changein State Deferred Tax Rate EffectiveIncomeTaxRateReconciliationChangeinStateDeferredTaxRate	0	USD
CY2018	oas	Effective Income Tax Rate Reconciliation Changein State Deferred Tax Rate Percent EffectiveIncomeTaxRateReconciliationChangeinStateDeferredTaxRatePercent	-0.1373
CY2018	oas	Effective Income Tax Rate Reconciliation Changein State Deferred Tax Rate EffectiveIncomeTaxRateReconciliationChangeinStateDeferredTaxRate	3479000	USD
CY2017	oas	Effective Income Tax Rate Reconciliation Changein State Deferred Tax Rate Percent EffectiveIncomeTaxRateReconciliationChangeinStateDeferredTaxRatePercent	-0.0036
CY2017	oas	Effective Income Tax Rate Reconciliation Changein State Deferred Tax Rate EffectiveIncomeTaxRateReconciliationChangeinStateDeferredTaxRate	270000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-0.0674
CY2018	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	1707000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	0
CY2017	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	0	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2019	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	0	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.0734
CY2018	us-gaap	Income Tax Reconciliation Change In Enacted Tax Rate IncomeTaxReconciliationChangeInEnactedTaxRate	1859000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	2.2661
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther	-0.0033
CY2019	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	402000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther	0.0041
CY2018	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	-104000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther	-0.0015
CY2017	us-gaap	Income Tax Reconciliation Nondeductible Expense Other IncomeTaxReconciliationNondeductibleExpenseOther	111000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2652
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-32715000	USD
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.2305
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5843000	USD
CY2017	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	2.6801
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-203304000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	191022000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	177745000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	8799000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation	8436000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	3946000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other Tax Carryforwards DeferredTaxAssetsOtherTaxCarryforwards	1643000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Other Tax Carryforwards DeferredTaxAssetsOtherTaxCarryforwards	856000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	205410000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	187037000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	2915000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	2863000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	202495000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	184174000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	426130000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	423270000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	0	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Derivatives DeferredTaxLiabilitiesDerivatives	22834000	USD
CY2019Q4	oas	Deferred Tax Liabilities Investmentin Subsidiaries DeferredTaxLiabilitiesInvestmentinSubsidiaries	38015000	USD
CY2018Q4	oas	Deferred Tax Liabilities Investmentin Subsidiaries DeferredTaxLiabilitiesInvestmentinSubsidiaries	22450000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	5707000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	15675000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	469852000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	484229000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	267357000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	300055000	USD
CY2019Q4	us-gaap	Operating Loss Carryforwards Valuation Allowance OperatingLossCarryforwardsValuationAllowance	2900000	USD
CY2018Q4	us-gaap	Operating Loss Carryforwards Valuation Allowance OperatingLossCarryforwardsValuationAllowance	2900000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	16050000	shares
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	7800000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6800000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	6300000	USD
CY2019	us-gaap	Dilutive Securities DilutiveSecurities	0	USD
CY2017	us-gaap	Dilutive Securities DilutiveSecurities	0	USD
CY2018	us-gaap	Dilutive Securities DilutiveSecurities	0	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	315002000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	307480000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	234986000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	315002000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	307480000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	237875000	shares
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	143968000	USD
CY2017	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2881000	shares
CY2018	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	384228000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1293719000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1293719000	USD
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CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	9242000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	6980000	shares
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	Segment
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3	Segment
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2071744000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2071744000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	154423000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-277785000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-123362000	USD
CY2019Q4	us-gaap	Assets Assets	7499253000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6977776000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	2413000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	2543000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	260000	USD
CY2019	oas	Capital Expenditures Cashand Non Cash CapitalExpendituresCashandNonCash	843368000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	787192000	USD
CY2019	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	143506000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	33607000	USD
CY2019	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	10257000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2321947000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2321947000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	119012000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-144355000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-25343000	USD
CY2018Q4	us-gaap	Assets Assets	7626142000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	7027109000	USD
CY2018	oas	Capital Expenditures Cashand Non Cash CapitalExpendituresCashandNonCash	2203453000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	636296000	USD
CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	121346000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	29273000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	26534000	USD
CY2017	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	6887000	USD
CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-219826000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	530802000	USD
CY2017	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	91797000	USD
CY2019	us-gaap	Lease Cost LeaseCost	42990000	USD
CY2017Q4	us-gaap	Assets Assets	6622929000	USD
CY2017Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6173486000	USD
CY2017	oas	Capital Expenditures Cashand Non Cash CapitalExpendituresCashandNonCash	836204000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	26341000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	9189000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	4657000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	10600000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	44362000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	18497000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2362000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	7001000	USD
CY2017	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	6900000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	2585000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	2704000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	2038000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	3073000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1367000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	2365000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	274000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	24097000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	6303000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	45000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	10440000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	639000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	27945000	USD
CY2019Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	6948000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	3848000	USD
CY2019Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	578000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	6370000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	8723000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	7009000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	6005000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	5130000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	4361000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	13134000	USD
CY2019Q4	oas	Lessee Right Of Use Asset LesseeRightOfUseAsset	24800000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	6182000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	17915000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	3958000	USD
CY2019Q4	oas	Lessee Lease Liability LesseeLeaseLiability	30468000	USD
CY2019Q4	oas	Finance Lease Right Of Use Asset Accumulated Depreciation FinanceLeaseRightOfUseAssetAccumulatedDepreciation	2300000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	30316000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	260000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2382000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	12746000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	3433000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y1M6D
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CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P4Y1M6D
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.039
CY2019Q4	us-gaap	Other Commitment Due In Next Twelve Months OtherCommitmentDueInNextTwelveMonths	82515000	USD
CY2019Q4	us-gaap	Other Commitment Due In Second Year OtherCommitmentDueInSecondYear	95074000	USD
CY2019Q4	us-gaap	Other Commitment Due In Third Year OtherCommitmentDueInThirdYear	107004000	USD
CY2019Q4	us-gaap	Other Commitment Due In Fourth Year OtherCommitmentDueInFourthYear	91649000	USD
CY2019Q4	us-gaap	Other Commitment Due In Fifth Year OtherCommitmentDueInFifthYear	78013000	USD
CY2019Q4	us-gaap	Other Commitment Due After Fifth Year OtherCommitmentDueAfterFifthYear	140282000	USD
CY2019Q4	us-gaap	Other Commitment OtherCommitment	594537000	USD
CY2019Q4	us-gaap	Loss Contingency Accrual At Carrying Value LossContingencyAccrualAtCarryingValue	20000000	USD
CY2019	oas	Ownership Percentage Guarantor OwnershipPercentageGuarantor	1
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	20019000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	371181000	USD
CY2019Q4	us-gaap	Due From Affiliate Current DueFromAffiliateCurrent	0	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	35259000	USD
CY2019Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	10011000	USD
CY2019Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	535000	USD
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	346000	USD
CY2019Q4	us-gaap	Assets Current AssetsCurrent	437351000	USD
CY2019Q4	us-gaap	Oil And Gas Property Successful Effort Method Gross OilAndGasPropertySuccessfulEffortMethodGross	9463038000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	1279653000	USD
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CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7626142000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6977776000	USD
CY2019Q4	us-gaap	Disposal Group Including Discontinued Operation Assets Noncurrent DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent	21628000	USD
CY2019Q4	oas	Investments In And Advances To Affiliates InvestmentsInAndAdvancesToAffiliates	0	USD
CY2019Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	639000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	0	USD
CY2019Q4	us-gaap	Inventory Noncurrent InventoryNoncurrent	13924000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	18497000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	29438000	USD
CY2019Q4	us-gaap	Assets Assets	7499253000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	17948000	USD
CY2019Q4	us-gaap	Due To Affiliate Current DueToAffiliateCurrent	0	USD
CY2019Q4	oas	Revenues Payable And Production Taxes Current RevenuesPayableAndProductionTaxesCurrent	233090000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	281079000	USD
CY2019Q4	us-gaap	Interest Payable Current InterestPayableCurrent	37388000	USD
CY2019Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	19695000	USD
CY2019Q4	oas	Advances From Joint Interest Partners Current AdvancesFromJointInterestPartnersCurrent	4598000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	6182000	USD
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	2903000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	602883000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2711573000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	267357000	USD
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CY2019Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	120000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	17915000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	6019000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	3662172000	USD
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CY2019Q4	us-gaap	Minority Interest MinorityInterest	200943000	USD
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CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7499253000	USD
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CY2018Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	10997000	USD
CY2018Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	99930000	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	125000	USD
CY2018Q4	us-gaap	Other Assets Current OtherAssetsCurrent	183000	USD
CY2018Q4	us-gaap	Assets Current AssetsCurrent	554155000	USD
CY2018Q4	us-gaap	Oil And Gas Property Successful Effort Method Gross OilAndGasPropertySuccessfulEffortMethodGross	8912189000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Other PropertyPlantAndEquipmentOther	1151772000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	3036852000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	7027109000	USD
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CY2018Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	6945000	USD
CY2018Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	0	USD
CY2018Q4	us-gaap	Inventory Noncurrent InventoryNoncurrent	12260000	USD
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CY2018Q4	us-gaap	Minority Interest MinorityInterest	184304000	USD
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CY2018Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	52384000	USD
CY2018Q4	us-gaap	Assets Assets	7626142000	USD
CY2018Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	20166000	USD
CY2018Q4	us-gaap	Due To Affiliate Current DueToAffiliateCurrent	0	USD
CY2018Q4	oas	Revenues Payable And Production Taxes Current RevenuesPayableAndProductionTaxesCurrent	216695000	USD
CY2018Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	331651000	USD
CY2018Q4	us-gaap	Interest Payable Current InterestPayableCurrent	38040000	USD
CY2018Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	84000	USD
CY2018Q4	oas	Advances From Joint Interest Partners Current AdvancesFromJointInterestPartnersCurrent	5140000	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	611776000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	2735276000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	300055000	USD
CY2018Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	20000	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	7751000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	3707262000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	3734576000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2071744000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	223384000	USD
CY2019	us-gaap	Results Of Operations Transportation Costs ResultsOfOperationsTransportationCosts	128806000	USD
CY2019	us-gaap	Production Tax Expense ProductionTaxExpense	112592000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	787192000	USD
CY2019	us-gaap	Exploration Expense ExplorationExpense	6658000	USD
CY2019	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	384000	USD
CY2019	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	10257000	USD
CY2019	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	143506000	USD
CY2019	us-gaap	Costs And Expenses CostsAndExpenses	1912866000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	-4455000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	154423000	USD
CY2019	oas	Equity In Earnings In Subsidiaries EquityInEarningsInSubsidiaries	0	USD
CY2019	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-106314000	USD
CY2019	us-gaap	Interest Expense InterestExpense	176223000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	37596000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	127446000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	-128243000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2321947000	USD
CY2018	us-gaap	Operating Lease Expense OperatingLeaseExpense	193912000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4312000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	440000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-277785000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-123362000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-32715000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	-90647000	USD
CY2018	us-gaap	Results Of Operations Transportation Costs ResultsOfOperationsTransportationCosts	107193000	USD
CY2018	us-gaap	Production Tax Expense ProductionTaxExpense	133696000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	636296000	USD
CY2018	us-gaap	Exploration Expense ExplorationExpense	27432000	USD
CY2018	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	384228000	USD
CY2018	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	121346000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-25343000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5843000	USD
CY2018	us-gaap	Costs And Expenses CostsAndExpenses	2231522000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	28587000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	119012000	USD
CY2018	oas	Equity In Earnings In Subsidiaries EquityInEarningsInSubsidiaries	0	USD
CY2018	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	28457000	USD
CY2018	us-gaap	Interest Expense InterestExpense	159085000	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-13848000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	121000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-144355000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	-19500000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	15796000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	-35296000	USD
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1293719000	USD
CY2017	us-gaap	Operating Lease Expense OperatingLeaseExpense	177134000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	53051000	USD
CY2017	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-71657000	USD
CY2017	us-gaap	Results Of Operations Transportation Costs ResultsOfOperationsTransportationCosts	55740000	USD
CY2017	us-gaap	Production Tax Expense ProductionTaxExpense	88133000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	530802000	USD
CY2017	us-gaap	Exploration Expense ExplorationExpense	11600000	USD
CY2017	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	6887000	USD
CY2017	us-gaap	General And Administrative Expense GeneralAndAdministrativeExpense	91797000	USD
CY2017	us-gaap	Costs And Expenses CostsAndExpenses	1151525000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	1774000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	143968000	USD
CY2017	oas	Equity In Earnings In Subsidiaries EquityInEarningsInSubsidiaries	0	USD
CY2017	us-gaap	Interest Expense InterestExpense	146837000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1332000	USD
CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-219826000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	-75858000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-203304000	USD
CY2019	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	-4455000	USD
CY2019	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	10257000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-32699000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	9789000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3650000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	123796000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	-90647000	USD
CY2019	oas	Equity In Earnings In Subsidiaries EquityInEarningsInSubsidiaries	0	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	787192000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	4312000	USD
CY2019	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-106314000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	33607000	USD
CY2019	oas	Debt Discount Amortization And Other DebtDiscountAmortizationAndOther	27263000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	-13729000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	5893000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	-325000	USD
CY2019	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	1972500000	USD
CY2019	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	45790000	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	1052000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2171000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	22190000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	892853000	USD
CY2019	us-gaap	Payments To Explore And Develop Oil And Gas Properties PaymentsToExploreAndDevelopOilAndGasProperties	869221000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	21009000	USD
CY2019	us-gaap	Proceeds From Sale Of Oil And Gas Property And Equipment ProceedsFromSaleOfOilAndGasPropertyAndEquipment	42376000	USD
CY2019	us-gaap	Proceeds From Derivative Instrument Investing Activities ProceedsFromDerivativeInstrumentInvestingActivities	19098000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-828756000	USD
CY2019	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	1982000000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	4856000	USD
CY2019	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	21270000	USD
CY2019	oas	Proceedsfrom Paymentsfor Contributionsfromto Affiliates ProceedsfromPaymentsforContributionsfromtoAffiliates	0	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	2382000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-418000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-66268000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	996421000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	20019000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	-19500000	USD
CY2018	oas	Equity In Earnings In Subsidiaries EquityInEarningsInSubsidiaries	0	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	636296000	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-13848000	USD
CY2018	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	28587000	USD
CY2018	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	384228000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5866000	USD
CY2018	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	28457000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	29273000	USD
CY2018	oas	Debt Discount Amortization And Other DebtDiscountAmortizationAndOther	29057000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	23508000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	14346000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	2354000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	26116000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-221000	USD
CY2017	us-gaap	Increase Decrease In Prepaid Expense IncreaseDecreaseInPrepaidExpense	838000	USD
CY2018	us-gaap	Payments To Explore And Develop Oil And Gas Properties PaymentsToExploreAndDevelopOilAndGasProperties	1148961000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	581650000	USD
CY2018	us-gaap	Proceeds From Sale Of Oil And Gas Property And Equipment ProceedsFromSaleOfOilAndGasPropertyAndEquipment	333229000	USD
CY2018	oas	Paymentsfor Costs Relatedto Divestitureof Businesses PaymentsforCostsRelatedtoDivestitureofBusinesses	2850000	USD
CY2018	us-gaap	Payments For Derivative Instrument Investing Activities PaymentsForDerivativeInstrumentInvestingActivities	213528000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-224000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-1613536000	USD
CY2018	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	3224000000	USD
CY2018	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	2586000000	USD
CY2018	us-gaap	Repayments Of Unsecured Debt RepaymentsOfUnsecuredDebt	423340000	USD
CY2018	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	400000000	USD
CY2018	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	13862000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Limited Partners Units ProceedsFromIssuanceOfCommonLimitedPartnersUnits	44503000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6846000	USD
CY2018	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	14114000	USD
CY2018	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	0	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	507876000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1756000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	622585000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5470000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	16720000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	22190000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	127446000	USD
CY2017	oas	Equity In Earnings In Subsidiaries EquityInEarningsInSubsidiaries	0	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	530802000	USD
CY2017	us-gaap	Gain Loss On Sale Of Property GainLossOnSaleOfProperty	1774000	USD
CY2017	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	6887000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-202884000	USD
CY2017	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-71657000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	26534000	USD
CY2017	oas	Debt Discount Amortization And Other DebtDiscountAmortizationAndOther	18311000	USD
CY2017	us-gaap	Increase Decrease In Accounts Receivable IncreaseDecreaseInAccountsReceivable	166386000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	2501000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable And Accrued Liabilities IncreaseDecreaseInAccountsPayableAndAccruedLiabilities	123107000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	22485000	USD
CY2019	us-gaap	Costs Incurred Acquisition Of Oil And Gas Properties CostsIncurredAcquisitionOfOilAndGasProperties	634744000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	302191000	USD
CY2018	us-gaap	Costs Incurred Acquisition Of Oil And Gas Properties CostsIncurredAcquisitionOfOilAndGasProperties	1939621000	USD
CY2017	us-gaap	Payments To Explore And Develop Oil And Gas Properties PaymentsToExploreAndDevelopOilAndGasProperties	647349000	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	61874000	USD
CY2017	us-gaap	Proceeds From Sale Of Oil And Gas Property And Equipment ProceedsFromSaleOfOilAndGasPropertyAndEquipment	5774000	USD
CY2017	oas	Paymentsfor Costs Relatedto Divestitureof Businesses PaymentsforCostsRelatedtoDivestitureofBusinesses	366000	USD
CY2017	us-gaap	Payments For Derivative Instrument Investing Activities PaymentsForDerivativeInstrumentInvestingActivities	8264000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	2681000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-714760000	USD
CY2017	us-gaap	Proceeds From Long Term Lines Of Credit ProceedsFromLongTermLinesOfCredit	1162000000	USD
CY2017	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	1377000000	USD
CY2017	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	2714000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Limited Partners Units ProceedsFromIssuanceOfCommonLimitedPartnersUnits	134185000	USD
CY2017	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6229000	USD
CY2017	oas	Proceedsfrom Paymentsfor Contributionsfromto Affiliates ProceedsfromPaymentsforContributionsfromtoAffiliates	0	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-55000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	212378000	USD
CY2017	srt	Proved Developed And Undeveloped Reserves Purchases Of Minerals In Place ProvedDevelopedAndUndevelopedReservesPurchasesOfMineralsInPlace	466	MBbls
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	5494000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	11226000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	16720000	USD
CY2019Q4	us-gaap	Proved Oil And Gas Property Successful Effort Method ProvedOilAndGasPropertySuccessfulEffortMethod	8724376000	USD
CY2018Q4	us-gaap	Proved Oil And Gas Property Successful Effort Method ProvedOilAndGasPropertySuccessfulEffortMethod	7878104000	USD
CY2019Q4	us-gaap	Oil And Gas Property Successful Effort Method Accumulated Depreciation Depletion And Amortization OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAndAmortization	3601019000	USD
CY2018Q4	us-gaap	Oil And Gas Property Successful Effort Method Accumulated Depreciation Depletion And Amortization OilAndGasPropertySuccessfulEffortMethodAccumulatedDepreciationDepletionAndAmortization	2853353000	USD
CY2019Q4	oas	Proved Oil And Gas Properties Net ProvedOilAndGasPropertiesNet	5123357000	USD
CY2018Q4	oas	Proved Oil And Gas Properties Net ProvedOilAndGasPropertiesNet	5024751000	USD
CY2019Q4	us-gaap	Unproved Oil And Gas Property Successful Effort Method UnprovedOilAndGasPropertySuccessfulEffortMethod	738662000	USD
CY2018Q4	us-gaap	Unproved Oil And Gas Property Successful Effort Method UnprovedOilAndGasPropertySuccessfulEffortMethod	1034085000	USD
CY2019Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Net CapitalizedCostsOilAndGasProducingActivitiesNet	5862019000	USD
CY2018Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Net CapitalizedCostsOilAndGasProducingActivitiesNet	6058836000	USD
CY2019	us-gaap	Costs Incurred Asset Retirement Obligation Incurred CostsIncurredAssetRetirementObligationIncurred	2083000	USD
CY2018	us-gaap	Costs Incurred Asset Retirement Obligation Incurred CostsIncurredAssetRetirementObligationIncurred	5804000	USD
CY2017	us-gaap	Costs Incurred Asset Retirement Obligation Incurred CostsIncurredAssetRetirementObligationIncurred	-2965000	USD
CY2018Q4	srt	Proved Developed Reserves Volume ProvedDevelopedReservesVolume	144533	MBbls
CY2019	us-gaap	Costs Incurred Acquisition Of Oil And Gas Properties With Proved Reserves CostsIncurredAcquisitionOfOilAndGasPropertiesWithProvedReserves	0	USD
CY2018	us-gaap	Costs Incurred Acquisition Of Oil And Gas Properties With Proved Reserves CostsIncurredAcquisitionOfOilAndGasPropertiesWithProvedReserves	260034000	USD
CY2017	us-gaap	Costs Incurred Acquisition Of Oil And Gas Properties With Proved Reserves CostsIncurredAcquisitionOfOilAndGasPropertiesWithProvedReserves	61874000	USD
CY2019	us-gaap	Costs Incurred Acquisition Of Unproved Oil And Gas Properties CostsIncurredAcquisitionOfUnprovedOilAndGasProperties	23058000	USD
CY2018	us-gaap	Costs Incurred Acquisition Of Unproved Oil And Gas Properties CostsIncurredAcquisitionOfUnprovedOilAndGasProperties	696293000	USD
CY2017	us-gaap	Costs Incurred Acquisition Of Unproved Oil And Gas Properties CostsIncurredAcquisitionOfUnprovedOilAndGasProperties	5424000	USD
CY2019	us-gaap	Costs Incurred Exploration Costs CostsIncurredExplorationCosts	67470000	USD
CY2018	us-gaap	Costs Incurred Exploration Costs CostsIncurredExplorationCosts	53928000	USD
CY2017	us-gaap	Costs Incurred Exploration Costs CostsIncurredExplorationCosts	11600000	USD
CY2019	us-gaap	Costs Incurred Development Costs CostsIncurredDevelopmentCosts	542133000	USD
CY2018	us-gaap	Costs Incurred Development Costs CostsIncurredDevelopmentCosts	923562000	USD
CY2017	us-gaap	Costs Incurred Development Costs CostsIncurredDevelopmentCosts	511905000	USD
CY2017	us-gaap	Results Of Operations Depreciation Depletion And Amortization And Valuation Provisions ResultsOfOperationsDepreciationDepletionAndAmortizationAndValuationProvisions	515600000	USD
CY2019	us-gaap	Exploration Expense ExplorationExpense	6658000	USD
CY2019	us-gaap	Results Of Operations Income Tax Expense ResultsOfOperationsIncomeTaxExpense	40745000	USD
CY2017	us-gaap	Costs Incurred Acquisition Of Oil And Gas Properties CostsIncurredAcquisitionOfOilAndGasProperties	587838000	USD
CY2019	us-gaap	Results Of Operations Production Or Lifting Costs ResultsOfOperationsProductionOrLiftingCosts	464782000	USD
CY2018	us-gaap	Results Of Operations Production Or Lifting Costs ResultsOfOperationsProductionOrLiftingCosts	434801000	USD
CY2017	us-gaap	Results Of Operations Production Or Lifting Costs ResultsOfOperationsProductionOrLiftingCosts	321007000	USD
CY2019	us-gaap	Results Of Operations Depreciation Depletion And Amortization And Valuation Provisions ResultsOfOperationsDepreciationDepletionAndAmortizationAndValuationProvisions	759900000	USD
CY2018	us-gaap	Results Of Operations Depreciation Depletion And Amortization And Valuation Provisions ResultsOfOperationsDepreciationDepletionAndAmortizationAndValuationProvisions	613928000	USD
CY2018	us-gaap	Exploration Expense ExplorationExpense	27432000	USD
CY2017	us-gaap	Exploration Expense ExplorationExpense	11600000	USD
CY2019	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	384000	USD
CY2018	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	0	USD
CY2017	us-gaap	Disposal Group Not Discontinued Operation Loss Gain On Write Down DisposalGroupNotDiscontinuedOperationLossGainOnWriteDown	0	USD
CY2019	us-gaap	Results Of Operations Impairment Of Oil And Gas Properties ResultsOfOperationsImpairmentOfOilAndGasProperties	5389000	USD
CY2018	us-gaap	Results Of Operations Impairment Of Oil And Gas Properties ResultsOfOperationsImpairmentOfOilAndGasProperties	384228000	USD
CY2017	us-gaap	Results Of Operations Impairment Of Oil And Gas Properties ResultsOfOperationsImpairmentOfOilAndGasProperties	6887000	USD
CY2017	srt	Proved Developed And Undeveloped Reserves Sales Of Minerals In Place ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace	1147	MMcf
CY2018	us-gaap	Results Of Operations Income Tax Expense ResultsOfOperationsIncomeTaxExpense	30770000	USD
CY2017	us-gaap	Results Of Operations Income Tax Expense ResultsOfOperationsIncomeTaxExpense	67148000	USD
CY2019	us-gaap	Results Of Operations Oil And Gas Producing Activities Net Income Excluding Corporate Overhead And Interest Costs ResultsOfOperationsOilAndGasProducingActivitiesNetIncomeExcludingCorporateOverheadAndInterestCosts	130913000	USD
CY2018	us-gaap	Results Of Operations Oil And Gas Producing Activities Net Income Excluding Corporate Overhead And Interest Costs ResultsOfOperationsOilAndGasProducingActivitiesNetIncomeExcludingCorporateOverheadAndInterestCosts	98865000	USD
CY2017	us-gaap	Results Of Operations Oil And Gas Producing Activities Net Income Excluding Corporate Overhead And Interest Costs ResultsOfOperationsOilAndGasProducingActivitiesNetIncomeExcludingCorporateOverheadAndInterestCosts	112392000	USD
CY2016Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	236593	MBbls
CY2016Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	411104	MMcf
CY2016Q4	srt	Proved Developed And Undeveloped Reserve Net Energy ProvedDevelopedAndUndevelopedReserveNetEnergy	305110	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserves Revisions Of Previous Estimates Increase Decrease ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease	-28323	MBbls
CY2017	srt	Proved Developed And Undeveloped Reserves Revisions Of Previous Estimates Increase Decrease ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease	54726	MMcf
CY2017	srt	Proved Developed And Undeveloped Reserve Revision Of Previous Estimate Energy ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy	-19200	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserves Extensions Discoveries And Additions ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions	36238	MBbls
CY2017	srt	Proved Developed And Undeveloped Reserves Extensions Discoveries And Additions ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions	89489	MMcf
CY2017	srt	Proved Developed And Undeveloped Reserve Extension And Discovery Energy ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy	51153	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserves Sales Of Minerals In Place ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace	1196	MBbls
CY2017	srt	Proved Developed And Undeveloped Reserves Sale Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy	1387	MBoe
CY2017Q4	srt	Proved Developed Reserves Volume ProvedDevelopedReservesVolume	301101	MMcf
CY2017Q4	srt	Proved Developed And Undeveloped Reserve Net Energy ProvedDevelopedAndUndevelopedReserveNetEnergy	312204	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserves Purchases Of Minerals In Place ProvedDevelopedAndUndevelopedReservesPurchasesOfMineralsInPlace	1230	MMcf
CY2017	srt	Proved Developed And Undeveloped Reserve Purchase Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservePurchaseOfMineralInPlaceEnergy	671	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserves Production ProvedDevelopedAndUndevelopedReservesProduction	18818	MBbls
CY2017	srt	Proved Developed And Undeveloped Reserves Production ProvedDevelopedAndUndevelopedReservesProduction	31946	MMcf
CY2017	srt	Proved Developed And Undeveloped Reserve Production Energy ProvedDevelopedAndUndevelopedReserveProductionEnergy	24143	MBoe
CY2017Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	224960	MBbls
CY2017Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	523456	MMcf
CY2017Q4	srt	Proved Developed And Undeveloped Reserve Net Energy ProvedDevelopedAndUndevelopedReserveNetEnergy	312204	MBoe
CY2017Q4	srt	Proved Developed Reserves Volume ProvedDevelopedReservesVolume	150628	MBbls
CY2017Q4	srt	Proved Developed Reserves Boe1 ProvedDevelopedReservesBOE1	200812	MBoe
CY2017Q4	srt	Proved Undeveloped Reserve Volume ProvedUndevelopedReserveVolume	74332	MBbls
CY2017Q4	srt	Proved Undeveloped Reserve Volume ProvedUndevelopedReserveVolume	222355	MMcf
CY2017Q4	srt	Proved Undeveloped Reserve Boe1 ProvedUndevelopedReserveBOE1	111392	MBoe
CY2017Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	224960	MBbls
CY2017Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	523456	MMcf
CY2018Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	552726	MMcf
CY2018Q4	srt	Proved Developed And Undeveloped Reserve Net Energy ProvedDevelopedAndUndevelopedReserveNetEnergy	320537	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserves Revisions Of Previous Estimates Increase Decrease ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease	-17352	MBbls
CY2018	srt	Proved Developed And Undeveloped Reserves Revisions Of Previous Estimates Increase Decrease ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease	3019	MMcf
CY2018	srt	Proved Developed And Undeveloped Reserve Revision Of Previous Estimate Energy ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy	-16850	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserves Extensions Discoveries And Additions ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions	30640	MBbls
CY2018	srt	Proved Developed And Undeveloped Reserves Extensions Discoveries And Additions ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions	46309	MMcf
CY2018	srt	Proved Developed And Undeveloped Reserve Extension And Discovery Energy ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy	38358	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserves Sales Of Minerals In Place ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace	12470	MBbls
CY2018	srt	Proved Developed And Undeveloped Reserves Sales Of Minerals In Place ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace	20735	MMcf
CY2018	srt	Proved Developed And Undeveloped Reserves Sale Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy	15926	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserves Purchases Of Minerals In Place ProvedDevelopedAndUndevelopedReservesPurchasesOfMineralsInPlace	25688	MBbls
CY2018	srt	Proved Developed And Undeveloped Reserves Purchases Of Minerals In Place ProvedDevelopedAndUndevelopedReservesPurchasesOfMineralsInPlace	43107	MMcf
CY2018	srt	Proved Developed And Undeveloped Reserve Purchase Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservePurchaseOfMineralInPlaceEnergy	32873	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserves Production ProvedDevelopedAndUndevelopedReservesProduction	23050	MBbls
CY2018	srt	Proved Developed And Undeveloped Reserves Production ProvedDevelopedAndUndevelopedReservesProduction	42430	MMcf
CY2018	srt	Proved Developed And Undeveloped Reserve Production Energy ProvedDevelopedAndUndevelopedReserveProductionEnergy	30122	MBoe
CY2018Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	228416	MBbls
CY2018Q4	srt	Proved Developed And Undeveloped Reserve Net Energy ProvedDevelopedAndUndevelopedReserveNetEnergy	320537	MBoe
CY2019	srt	Proved Developed And Undeveloped Reserves Revisions Of Previous Estimates Increase Decrease ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease	-51965	MBbls
CY2019	srt	Proved Developed And Undeveloped Reserves Revisions Of Previous Estimates Increase Decrease ProvedDevelopedAndUndevelopedReservesRevisionsOfPreviousEstimatesIncreaseDecrease	-68301	MMcf
CY2019	srt	Proved Developed And Undeveloped Reserves Sale Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy	2531	MBoe
CY2018Q4	srt	Proved Developed Reserves Volume ProvedDevelopedReservesVolume	339444	MMcf
CY2018Q4	srt	Proved Developed Reserves Boe1 ProvedDevelopedReservesBOE1	201107	MBoe
CY2018Q4	srt	Proved Undeveloped Reserve Volume ProvedUndevelopedReserveVolume	83883	MBbls
CY2018Q4	srt	Proved Undeveloped Reserve Volume ProvedUndevelopedReserveVolume	213282	MMcf
CY2018Q4	srt	Proved Undeveloped Reserve Boe1 ProvedUndevelopedReserveBOE1	119430	MBoe
CY2018Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	228416	MBbls
CY2018Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	552726	MMcf
CY2019	srt	Proved Developed And Undeveloped Reserve Revision Of Previous Estimate Energy ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy	-63349	MBoe
CY2019	srt	Proved Developed And Undeveloped Reserves Extensions Discoveries And Additions ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions	49297	MBbls
CY2019	srt	Proved Developed And Undeveloped Reserves Extensions Discoveries And Additions ProvedDevelopedAndUndevelopedReservesExtensionsDiscoveriesAndAdditions	87382	MMcf
CY2019	srt	Proved Developed And Undeveloped Reserve Extension And Discovery Energy ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy	63861	MBoe
CY2019	srt	Proved Developed And Undeveloped Reserves Sales Of Minerals In Place ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace	2136	MBbls
CY2019	srt	Proved Developed And Undeveloped Reserves Sales Of Minerals In Place ProvedDevelopedAndUndevelopedReservesSalesOfMineralsInPlace	2368	MMcf
CY2018	srt	Proved Developed And Undeveloped Reserve Extension And Discovery Energy ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy	38400	MBoe
CY2019Q4	srt	Proved Developed Reserves Volume ProvedDevelopedReservesVolume	113418	MBbls
CY2018	oas	Estimated Extensions And Discoveries Of Reserves Associated With New Wells EstimatedExtensionsAndDiscoveriesOfReservesAssociatedWithNewWells	9000.0	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserve Revision Of Previous Estimate Energy ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy	-19200	MBoe
CY2019Q4	srt	Proved Developed Reserves Volume ProvedDevelopedReservesVolume	314000	MMcf
CY2019	srt	Proved Developed And Undeveloped Reserves Production ProvedDevelopedAndUndevelopedReservesProduction	22825	MBbls
CY2019	srt	Proved Developed And Undeveloped Reserves Production ProvedDevelopedAndUndevelopedReservesProduction	55906	MMcf
CY2019	srt	Proved Developed And Undeveloped Reserve Production Energy ProvedDevelopedAndUndevelopedReserveProductionEnergy	32142	MBoe
CY2019Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	200787	MBbls
CY2019Q4	srt	Proved Developed And Undeveloped Reserves Net ProvedDevelopedAndUndevelopedReservesNet	513533	MMcf
CY2019Q4	srt	Proved Developed And Undeveloped Reserve Net Energy ProvedDevelopedAndUndevelopedReserveNetEnergy	286376	MBoe
CY2019Q4	srt	Proved Developed Reserves Boe1 ProvedDevelopedReservesBOE1	165751	MBoe
CY2019Q4	srt	Proved Undeveloped Reserve Volume ProvedUndevelopedReserveVolume	87369	MBbls
CY2019Q4	srt	Proved Undeveloped Reserve Volume ProvedUndevelopedReserveVolume	199533	MMcf
CY2019Q4	srt	Proved Undeveloped Reserve Boe1 ProvedUndevelopedReserveBOE1	120625	MBoe
CY2019	srt	Proved Developed And Undeveloped Reserve Revision Of Previous Estimate Energy ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy	-63300	MBoe
CY2019	oas	Proved Developedand Undeveloped Reserve Revisionof Previous Estimate Percentage ProvedDevelopedandUndevelopedReserveRevisionofPreviousEstimatePercentage	-0.20
CY2018	srt	Proved Developed And Undeveloped Reserve Revision Of Previous Estimate Energy ProvedDevelopedAndUndevelopedReserveRevisionOfPreviousEstimateEnergy	-16900	MBoe
CY2018	oas	Proved Developedand Undeveloped Reserve Revisionof Previous Estimate Percentage ProvedDevelopedandUndevelopedReserveRevisionofPreviousEstimatePercentage	-0.05
CY2018	oas	Proved Developed Reserve Revisionof Previous Estimate ProvedDevelopedReserveRevisionofPreviousEstimate	-20200	MBoe
CY2018	oas	Percentage Of Reserves Produced From Wells PercentageOfReservesProducedFromWells	0.77
CY2019	oas	Estimated Extensions And Discoveries Of Reserves Associated With New Wells EstimatedExtensionsAndDiscoveriesOfReservesAssociatedWithNewWells	10300	MBoe
CY2019	oas	Additional Proved Undeveloped Reserves AdditionalProvedUndevelopedReserves	53600	MBoe
CY2019	srt	Proved Developed And Undeveloped Reserve Purchase Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservePurchaseOfMineralInPlaceEnergy	0	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserve Purchase Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservePurchaseOfMineralInPlaceEnergy	32900	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserve Purchase Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservePurchaseOfMineralInPlaceEnergy	700	MBoe
CY2019	oas	Percentage Of Reserves Produced From Wells PercentageOfReservesProducedFromWells	0.63
CY2018	oas	Additional Proved Undeveloped Reserves AdditionalProvedUndevelopedReserves	29400	MBoe
CY2019	oas	Unweighted Arithmetic Average First Day Of Month Prices UnweightedArithmeticAverageFirstDayOfMonthPrices	55.85
CY2017	oas	Proved Developedand Undeveloped Reserve Revisionof Previous Estimate Percentage ProvedDevelopedandUndevelopedReserveRevisionofPreviousEstimatePercentage	-0.06
CY2017	oas	Proved Developed Reserve Revisionof Previous Estimate ProvedDevelopedReserveRevisionofPreviousEstimate	-14200	MBoe
CY2017	oas	Proved Undeveloped Reserve Revisionof Previous Estimate ProvedUndevelopedReserveRevisionofPreviousEstimate	-5000.0	MBoe
CY2019	srt	Proved Developed And Undeveloped Reserve Extension And Discovery Energy ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy	63900	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserve Extension And Discovery Energy ProvedDevelopedAndUndevelopedReserveExtensionAndDiscoveryEnergy	51200	MBoe
CY2017	oas	Estimated Extensions And Discoveries Of Reserves Associated With New Wells EstimatedExtensionsAndDiscoveriesOfReservesAssociatedWithNewWells	17900	MBoe
CY2017	oas	Percentage Of Reserves Produced From Wells PercentageOfReservesProducedFromWells	1
CY2017	oas	Additional Proved Undeveloped Reserves AdditionalProvedUndevelopedReserves	33300	MBoe
CY2017	oas	Percentage Of Proved Undeveloped Reserves PercentageOfProvedUndevelopedReserves	1
CY2019	srt	Proved Developed And Undeveloped Reserves Sale Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy	2500	MBoe
CY2018	srt	Proved Developed And Undeveloped Reserves Sale Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy	15900	MBoe
CY2017	srt	Proved Developed And Undeveloped Reserves Sale Of Mineral In Place Energy ProvedDevelopedAndUndevelopedReservesSaleOfMineralInPlaceEnergy	1400	MBoe
CY2019	oas	Unweighted Arithmetic Average First Day Of Month Prices For Natural Gas UnweightedArithmeticAverageFirstDayOfMonthPricesForNaturalGas	2.62
CY2018	oas	Unweighted Arithmetic Average First Day Of Month Prices UnweightedArithmeticAverageFirstDayOfMonthPrices	65.66
CY2018Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Net Cash Flows FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows	7373170000	USD
CY2017Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Net Cash Flows FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows	5604956000	USD
CY2019Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Ten Percent Annual Discount For Estimated Timing Of Cash Flows FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows	2352200000	USD
CY2019Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Development Costs FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts	1490521000	USD
CY2017	srt	Net Increase Decrease In Sales And Transfer Prices And Production Costs NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts	881742000	USD
CY2018	oas	Unweighted Arithmetic Average First Day Of Month Prices For Natural Gas UnweightedArithmeticAverageFirstDayOfMonthPricesForNaturalGas	3.16
CY2017	oas	Unweighted Arithmetic Average First Day Of Month Prices UnweightedArithmeticAverageFirstDayOfMonthPrices	51.34
CY2017	oas	Unweighted Arithmetic Average First Day Of Month Prices For Natural Gas UnweightedArithmeticAverageFirstDayOfMonthPricesForNaturalGas	2.99
CY2019Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Cash Inflows FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows	12385040000	USD
CY2018Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Cash Inflows FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows	16652405000	USD
CY2017Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Cash Inflows FutureNetCashFlowsRelatingToProvedOilAndGasReservesCashInflows	11636126000	USD
CY2019Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Production Costs FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts	5509127000	USD
CY2018Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Production Costs FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts	6609097000	USD
CY2017Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Production Costs FutureNetCashFlowsRelatingToProvedOilAndGasReservesProductionCosts	4458418000	USD
CY2018Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Development Costs FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts	1701672000	USD
CY2017Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Development Costs FutureNetCashFlowsRelatingToProvedOilAndGasReservesDevelopmentCosts	992271000	USD
CY2019Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Income Tax Expense FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense	188823000	USD
CY2018Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Income Tax Expense FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense	968466000	USD
CY2017Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Income Tax Expense FutureNetCashFlowsRelatingToProvedOilAndGasReservesIncomeTaxExpense	580481000	USD
CY2019Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Net Cash Flows FutureNetCashFlowsRelatingToProvedOilAndGasReservesNetCashFlows	5196569000	USD
CY2019	srt	Net Increase Decrease In Sales And Transfer Prices And Production Costs NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts	-1070192000	USD
CY2018Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Ten Percent Annual Discount For Estimated Timing Of Cash Flows FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows	3322864000	USD
CY2018	srt	Net Increase Decrease In Sales And Transfer Prices And Production Costs NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts	1003008000	USD
CY2017Q4	srt	Future Net Cash Flows Relating To Proved Oil And Gas Reserves Ten Percent Annual Discount For Estimated Timing Of Cash Flows FutureNetCashFlowsRelatingToProvedOilAndGasReservesTenPercentAnnualDiscountForEstimatedTimingOfCashFlows	2304261000	USD
CY2019Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	2844369000	USD
CY2018Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	4050306000	USD
CY2017Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	3300695000	USD
CY2018Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	4050306000	USD
CY2017Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	3300695000	USD
CY2016Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	2483065000	USD
CY2019	srt	Increase Decrease In Estimated Future Development Costs IncreaseDecreaseInEstimatedFutureDevelopmentCosts	131003000	USD
CY2018	srt	Increase Decrease In Estimated Future Development Costs IncreaseDecreaseInEstimatedFutureDevelopmentCosts	-89304000	USD
CY2017	srt	Increase Decrease In Estimated Future Development Costs IncreaseDecreaseInEstimatedFutureDevelopmentCosts	-60929000	USD
CY2019	srt	Sales And Transfers Of Oil And Gas Produced Net Of Production Costs SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts	943989000	USD
CY2018	srt	Sales And Transfers Of Oil And Gas Produced Net Of Production Costs SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts	1155223000	USD
CY2017	srt	Sales And Transfers Of Oil And Gas Produced Net Of Production Costs SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts	769367000	USD
CY2019	srt	Increase Due To Purchases Of Minerals In Place IncreaseDueToPurchasesOfMineralsInPlace	0	USD
CY2018	srt	Increase Due To Purchases Of Minerals In Place IncreaseDueToPurchasesOfMineralsInPlace	385763000	USD
CY2017	srt	Increase Due To Purchases Of Minerals In Place IncreaseDueToPurchasesOfMineralsInPlace	6518000	USD
CY2019	srt	Decrease Due To Sales Of Minerals In Place DecreaseDueToSalesOfMineralsInPlace	36907000	USD
CY2018	srt	Decrease Due To Sales Of Minerals In Place DecreaseDueToSalesOfMineralsInPlace	197867000	USD
CY2017	srt	Decrease Due To Sales Of Minerals In Place DecreaseDueToSalesOfMineralsInPlace	9024000	USD
CY2019	srt	Revisions Of Previous Quantity Estimates RevisionsOfPreviousQuantityEstimates	-732253000	USD
CY2018	srt	Revisions Of Previous Quantity Estimates RevisionsOfPreviousQuantityEstimates	-115015000	USD
CY2017	srt	Revisions Of Previous Quantity Estimates RevisionsOfPreviousQuantityEstimates	-78942000	USD
CY2019	srt	Previously Estimated Development Costs Incurred PreviouslyEstimatedDevelopmentCostsIncurred	246311000	USD
CY2018	srt	Previously Estimated Development Costs Incurred PreviouslyEstimatedDevelopmentCostsIncurred	303364000	USD
CY2017	srt	Previously Estimated Development Costs Incurred PreviouslyEstimatedDevelopmentCostsIncurred	157386000	USD
CY2019	srt	Standardized Measure Of Discounted Future Net Cash Flow Relating To Proved Oil And Gas Reserves Accretion Of Discount StandardizedMeasureOfDiscountedFutureNetCashFlowRelatingToProvedOilAndGasReservesAccretionOfDiscount	467426000	USD
CY2018	srt	Standardized Measure Of Discounted Future Net Cash Flow Relating To Proved Oil And Gas Reserves Accretion Of Discount StandardizedMeasureOfDiscountedFutureNetCashFlowRelatingToProvedOilAndGasReservesAccretionOfDiscount	368374000	USD
CY2017	srt	Standardized Measure Of Discounted Future Net Cash Flow Relating To Proved Oil And Gas Reserves Accretion Of Discount StandardizedMeasureOfDiscountedFutureNetCashFlowRelatingToProvedOilAndGasReservesAccretionOfDiscount	262776000	USD
CY2019	srt	Increase Decrease In Future Income Tax Expense Estimates On Future Cash Flows Related To Proved Oil And Gas Reserves IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves	533872000	USD
CY2018	srt	Increase Decrease In Future Income Tax Expense Estimates On Future Cash Flows Related To Proved Oil And Gas Reserves IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves	-240908000	USD
CY2017	srt	Increase Decrease In Future Income Tax Expense Estimates On Future Cash Flows Related To Proved Oil And Gas Reserves IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves	-238354000	USD
CY2019	srt	Standardized Measure Of Discounted Future Net Cash Flow Of Proved Oil And Gas Reserves Other StandardizedMeasureOfDiscountedFutureNetCashFlowOfProvedOilAndGasReservesOther	-238908000	USD
CY2018	srt	Standardized Measure Of Discounted Future Net Cash Flow Of Proved Oil And Gas Reserves Other StandardizedMeasureOfDiscountedFutureNetCashFlowOfProvedOilAndGasReservesOther	26223000	USD
CY2017	srt	Standardized Measure Of Discounted Future Net Cash Flow Of Proved Oil And Gas Reserves Other StandardizedMeasureOfDiscountedFutureNetCashFlowOfProvedOilAndGasReservesOther	4357000	USD
CY2019Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	2844369000	USD
CY2018Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	4050306000	USD
CY2017Q4	srt	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	3300695000	USD
CY2019Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	575732000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	529405000	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	482743000	USD
CY2019Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	483864000	USD
CY2019Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	50444000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	71572000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	8441000	USD
CY2019Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	23966000	USD
CY2019Q1	us-gaap	Profit Loss ProfitLoss	-107978000	USD
CY2019Q2	us-gaap	Profit Loss ProfitLoss	51174000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	30311000	USD
CY2019Q4	us-gaap	Profit Loss ProfitLoss	-64154000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	-114882000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	42757000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	20288000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	-76406000	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.37
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.14
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.06
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.24
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.37
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.14
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.06
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.24
CY2018Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	473812000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	573751000	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	674629000	USD
CY2018Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	599755000	USD
CY2018Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	112985000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	-242674000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	179045000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	69656000	USD
CY2018Q1	us-gaap	Profit Loss ProfitLoss	3712000	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	-316301000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	66223000	USD
CY2018Q4	us-gaap	Profit Loss ProfitLoss	226866000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	590000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	-320204000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	62341000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	221977000	USD
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.00
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-1.02
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.20
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.00
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-1.02
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.20
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70

Files In Submission

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0001486159-20-000018-index-headers.html	Edgar Link	pending
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$CHRD
Chord Energy Corp Stock $chrd

2019 Q4 Form 10-K Financial Statement

#000148615920000018 Filed on February 27, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CHRD Chord Energy Corp Stock $chrd

2019 Q4 Form 10-K Financial Statement

#000148615920000018 Filed on February 27, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$CHRD
Chord Energy Corp Stock $chrd