$BKH
BLACK HILLS CORP /SD/ Stock $bkh

$bkh Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000113046421000007 Filed on February 26, 2021

Income Statement

Concept	2019 Q4	2018	2017 Q4
Revenue	$477.7M	$1.754B	$455.3M
YoY Change	-4.7%	4.4%	-0.02%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$400.0K	$12.40M
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$54.60M	$196.3M	$47.60M
YoY Change	9.2%	4.29%	36.39%
% of Gross Profit
Operating Expenses	$356.3M	$1.357B	$338.1M
YoY Change	-7.96%	7.42%	29.64%
Operating Profit	$121.4M	$397.0M	$117.2M
YoY Change	6.34%	-4.73%	6.22%
Interest Expense	-$30.60M	$140.0M	-$34.60M
YoY Change	-78.3%	2.1%	-4.16%
% of Operating Profit	-25.21%	35.25%	-29.52%
Other Income/Expense, Net	-$10.40M	-$141.2M	$100.0K
YoY Change	-109.76%	-6796.16%	-85.71%
Pretax Income	$80.40M	$255.9M	$82.70M
YoY Change	0.88%	-9.18%	-38.05%
Income Tax	$7.500M	-$23.67M	-$294.2M
% Of Pretax Income	9.33%	-9.25%	-355.74%
Net Earnings	$69.18M	$258.4M	$50.70M
YoY Change	-20.09%	45.98%	178.57%
Net Earnings / Revenue	14.48%	14.73%	11.14%
Basic Earnings Per Share	$1.13	$4.75	$0.95
Diluted Earnings Per Share	$1.13	$4.66	$0.92
COMMON SHARES
Basic Shares Outstanding	61.45M shares	54.42M shares	53.48M shares
Diluted Shares Outstanding		55.49M shares

Balance Sheet

Concept	2019 Q4	2018	2017 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$9.800M	$20.80M	$15.40M
YoY Change	-52.88%	35.06%	14.07%
Cash & Equivalents	$9.777M	$20.80M	$15.42M
Short-Term Investments
Other Short-Term Assets	$26.48M	$209.3M	$25.37M
YoY Change	-11.68%	-34.41%	6.01%
Inventory	$117.2M	$117.3M	$113.3M
Prepaid Expenses
Receivables	$255.8M	$143.5M	$248.3M
Other Receivables	$16.40M	$13.00M	$0.00
Total Short-Term Assets	$473.2M	$503.8M	$570.8M
YoY Change	-6.08%	-11.74%	22.27%
LONG-TERM ASSETS
Property, Plant & Equipment	$5.503B	$4.855B	$4.541B
YoY Change	13.35%	6.9%	3.54%
Goodwill	$1.299B		$1.299B
YoY Change	0.0%		0.0%
Intangibles	$13.27M		$7.559M
YoY Change	-7.47%		-9.93%
Long-Term Investments	$21.90M	$41.00M	$13.10M
YoY Change	-46.59%	212.98%	3.97%
Other Assets	$41.31M	$249.8M	$10.15M
YoY Change	187.8%	10.24%	-11.81%
Total Long-Term Assets	$7.085B	$6.460B	$6.088B
YoY Change	9.69%	6.1%	288.5%
TOTAL ASSETS
Total Short-Term Assets	$473.2M	$503.8M	$570.8M
Total Long-Term Assets	$7.085B	$6.460B	$6.088B
Total Assets	$7.558B	$6.963B	$6.659B
YoY Change	8.55%	4.57%	1.79%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$193.5M	$210.6M	$160.9M
YoY Change	-8.11%	30.89%	5.76%
Accrued Expenses	$226.8M	$129.4M	$219.5M
YoY Change	5.23%	-2.71%	-6.83%
Deferred Revenue
YoY Change
Short-Term Debt	$349.5M	$185.6M	$211.3M
YoY Change	88.29%	-12.16%	118.74%
Long-Term Debt Due	$5.743M	$5.700M	$5.743M
YoY Change	0.0%	0.0%	0.0%
Total Short-Term Liabilities	$811.3M	$648.2M	$649.1M
YoY Change	25.16%	-0.14%	22.95%
LONG-TERM LIABILITIES
Long-Term Debt	$3.140B	$2.951B	$3.109B
YoY Change	6.41%	-5.1%	-3.17%
Other Long-Term Liabilities	$124.7M	$1.077B	$105.7M
YoY Change	13.97%	-0.31%	-8.76%
Total Long-Term Liabilities	$3.265B	$4.028B	$1.080B
YoY Change	203.18%	-3.87%	1.12%
TOTAL LIABILITIES
Total Short-Term Liabilities	$811.3M	$648.2M	$649.1M
Total Long-Term Liabilities	$3.265B	$4.028B	$1.080B
Total Liabilities	$4.076B	$4.782B	$1.729B
YoY Change	136.28%	-3.4%	8.34%
SHAREHOLDERS EQUITY
Retained Earnings	$778.8M		$548.6M
YoY Change	11.19%		19.8%
Common Stock	$61.48M		$53.58M
YoY Change	2.38%		0.34%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$267.0K		$2.306M
YoY Change	-89.36%		191.53%
Treasury Stock Shares	3.956K shares		39.06K shares
Shareholders Equity	$2.362B	$2.182B	$1.709B
YoY Change
Total Liabilities & Shareholders Equity	$7.558B	$6.963B	$6.659B
YoY Change	8.55%	4.57%	1.79%

Cashflow Statement

Concept	2019 Q4	2018	2017 Q4
OPERATING ACTIVITIES
Net Income	$69.18M	$258.4M	$50.70M
YoY Change	-20.09%	45.98%	178.57%
Depreciation, Depletion And Amortization	$54.60M	$196.3M	$47.60M
YoY Change	9.2%	4.29%	36.39%
Cash From Operating Activities	$119.4M	$488.8M	$108.9M
YoY Change	8.45%	14.14%	-2.16%
INVESTING ACTIVITIES
Capital Expenditures	-$225.9M	$457.5M	-$87.20M
YoY Change	25.92%	40.34%	-27.87%
Acquisitions
YoY Change
Other Investing Activities	$2.900M	$4.281M	$26.00M
YoY Change	-161.7%	-523.44%	-398.85%
Cash From Investing Activities	-$222.9M	-$465.8M	-$61.10M
YoY Change	21.14%	46.9%	-52.82%
FINANCING ACTIVITIES
Cash Dividend Paid		$106.6M
YoY Change		10.18%
Common Stock Issuance & Retirement, Net		$300.8M
YoY Change		6724.73%
Debt Paid & Issued, Net		$854.7M
YoY Change		708.32%
Cash From Financing Activities	100.4M	-$17.06M	-45.60M
YoY Change	18.4%	-84.31%	-45700.0%
NET CHANGE
Cash From Operating Activities	119.4M	$488.8M	108.9M
Cash From Investing Activities	-222.9M	-$465.8M	-61.10M
Cash From Financing Activities	100.4M	-$17.06M	-45.60M
Net Change In Cash	-3.100M	$5.905M	2.200M
YoY Change	-128.44%	141.22%	-112.15%
FREE CASH FLOW
Cash From Operating Activities	$119.4M	$488.8M	$108.9M
Capital Expenditures	-$225.9M	$457.5M	-$87.20M
Free Cash Flow	$345.3M	$31.29M	$196.1M
YoY Change	19.27%	-69.4%	-15.55%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001130464
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-31303
CY2020	dei	Entity Registrant Name EntityRegistrantName	BLACK HILLS CORPORATION
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	SD
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	46-0458824
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	7001 Mount Rushmore Road
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Rapid City
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	SD
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	57702
CY2020	dei	City Area Code CityAreaCode	605
CY2020	dei	Local Phone Number LocalPhoneNumber	721-1700
CY2020	dei	Security12b Title Security12bTitle	Common stock of $1.00 par value
CY2020	dei	Trading Symbol TradingSymbol	BKH
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	3528768075	USD
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	62794490	shares
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CY2020	bkh	Fuel Purchased Power And Cost Of Gas Sold FuelPurchasedPowerAndCostOfGasSold	492404000	USD
CY2019	bkh	Fuel Purchased Power And Cost Of Gas Sold FuelPurchasedPowerAndCostOfGasSold	570829000	USD
CY2018	bkh	Fuel Purchased Power And Cost Of Gas Sold FuelPurchasedPowerAndCostOfGasSold	625610000	USD
CY2020	bkh	Operating Expense Maintenance Operationsand Other Costsand Expense OperatingExpenseMaintenanceOperationsandOtherCostsandExpense	495404000	USD
CY2019	bkh	Operating Expense Maintenance Operationsand Other Costsand Expense OperatingExpenseMaintenanceOperationsandOtherCostsandExpense	495994000	USD
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CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	0	USD
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CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansTax	958000	USD
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CY2020	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	-23000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	-19000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	-43000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	-80000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	-58000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Net Of Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditNetOfTax	-135000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3309000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3739000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7027000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	246072000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	209583000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	279689000	USD
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	15155000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	14012000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	14220000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	230917000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	195571000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	265469000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	6356000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	9777000	USD
CY2020Q4	us-gaap	Restricted Cash And Investments Current RestrictedCashAndInvestmentsCurrent	4383000	USD
CY2019Q4	us-gaap	Restricted Cash And Investments Current RestrictedCashAndInvestmentsCurrent	3881000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	265961000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	255805000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	117400000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	117172000	USD
CY2020Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	1848000	USD
CY2019Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	342000	USD
CY2020Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	19446000	USD
CY2019Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	16446000	USD
CY2020Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	51676000	USD
CY2019Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	43282000	USD
CY2020Q4	us-gaap	Other Assets Current OtherAssetsCurrent	26221000	USD
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	26479000	USD
CY2020Q4	us-gaap	Assets Current AssetsCurrent	493291000	USD
CY2019Q4	us-gaap	Assets Current AssetsCurrent	473184000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	7305530000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	6784679000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1285816000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1281493000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	6019714000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5503186000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	1299454000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	1299454000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	11944000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	13266000	USD
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	226582000	USD
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	228062000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	37801000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	41305000	USD
CY2020Q4	us-gaap	Assets Noncurrent Other Than Noncurrent Investments And Property Plant And Equipment AssetsNoncurrentOtherThanNoncurrentInvestmentsAndPropertyPlantAndEquipment	1575781000	USD
CY2019Q4	us-gaap	Assets Noncurrent Other Than Noncurrent Investments And Property Plant And Equipment AssetsNoncurrentOtherThanNoncurrentInvestmentsAndPropertyPlantAndEquipment	1582087000	USD
CY2020Q4	us-gaap	Assets Assets	8088786000	USD
CY2019Q4	us-gaap	Assets Assets	7558457000	USD
CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	183340000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	193523000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	243612000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	226767000	USD
CY2020Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	2044000	USD
CY2019Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	2254000	USD
CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	25061000	USD
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	33507000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	234040000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	349500000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	8436000	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	5743000	USD
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	696533000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	811294000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3528100000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	3140096000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	408624000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	360719000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	507659000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	503145000	USD
CY2020Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	150556000	USD
CY2019Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	154472000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	134667000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	124662000	USD
CY2020Q4	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	1201506000	USD
CY2019Q4	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	1142998000	USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
CY2019Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	62827179	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	61480658	shares
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	62827000	USD
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	61481000	USD
CY2020Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1657285000	USD
CY2019Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	1552788000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	870738000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	778776000	USD
CY2020Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	32492	shares
CY2019Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	3956	shares
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	2119000	USD
CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	267000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-27346000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-30655000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	2561385000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2362123000	USD
CY2020Q4	us-gaap	Noncontrolling Interest In Variable Interest Entity NoncontrollingInterestInVariableInterestEntity	101262000	USD
CY2019Q4	us-gaap	Noncontrolling Interest In Variable Interest Entity NoncontrollingInterestInVariableInterestEntity	101946000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2662647000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2464069000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	8088786000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7558457000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	242763000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	213322000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	272662000	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-6887000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	242763000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	213322000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	279549000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	224457000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	209120000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	196328000	USD
CY2020	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	7883000	USD
CY2019	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	7838000	USD
CY2018	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	7845000	USD
CY2020	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	6859000	USD
CY2019	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	19741000	USD
CY2018	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	0	USD
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	5373000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	12095000	USD
CY2018	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	45966000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	12390000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	38091000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	38020000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-24239000	USD
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	11997000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	12406000	USD
CY2018	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	14068000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-11669000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-16485000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-5836000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-2755000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-2052000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	2919000	USD
CY2020	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	10843000	USD
CY2019	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-7578000	USD
CY2020	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	24659000	USD
CY2019	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-34906000	USD
CY2018	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	5305000	USD
CY2020	us-gaap	Increase Decrease In Other Regulatory Assets IncreaseDecreaseInOtherRegulatoryAssets	5047000	USD
CY2019	us-gaap	Increase Decrease In Other Regulatory Assets IncreaseDecreaseInOtherRegulatoryAssets	-23619000	USD
CY2018	us-gaap	Increase Decrease In Other Regulatory Assets IncreaseDecreaseInOtherRegulatoryAssets	-33608000	USD
CY2020	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	-10706000	USD
CY2019	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	-15158000	USD
CY2018	us-gaap	Increase Decrease In Regulatory Liabilities IncreaseDecreaseInRegulatoryLiabilities	18533000	USD
CY2020	us-gaap	Pension Contributions PensionContributions	12700000	USD
CY2019	us-gaap	Pension Contributions PensionContributions	12700000	USD
CY2018	us-gaap	Pension Contributions PensionContributions	12700000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-4653000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-6001000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-6689000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	541863000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	505513000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	494327000	USD
CY2020	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	0	USD
CY2019	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	0	USD
CY2018	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	-5516000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	541863000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	505513000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	488811000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	767404000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	818376000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	457524000	USD
CY2020	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	0	USD
CY2019	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	0	USD
CY2018	us-gaap	Payments To Acquire Other Investments PaymentsToAcquireOtherInvestments	24429000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5740000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-2166000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4281000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-761664000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-816210000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-486234000	USD
CY2020	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	0	USD
CY2019	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	0	USD
CY2018	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	20385000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-761664000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-816210000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-465849000	USD
CY2020	us-gaap	Payments Of Dividends PaymentsOfDividends	135439000	USD
CY2019	us-gaap	Payments Of Dividends PaymentsOfDividends	124647000	USD
CY2018	us-gaap	Payments Of Dividends PaymentsOfDividends	106591000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	99278000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	101358000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	300834000	USD
CY2020	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-115460000	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	163880000	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt ProceedsFromRepaymentsOfShortTermDebt	-25680000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	400000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1100000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	700000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	8597000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	905743000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	854743000	USD
CY2020	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	15839000	USD
CY2019	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	17901000	USD
CY2018	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	19617000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7061000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-16737000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-11260000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	216882000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	300210000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-17057000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-2919000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-10487000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	5905000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	13658000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	24145000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	18240000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	10739000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	13658000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	24145000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	136549000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	131774000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	137965000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-2172000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-4682000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	14730000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	72215000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	91491000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	69017000	USD
CY2020	bkh	Non Cash Revision To Capitalized Asset Retirement Costs NonCashRevisionToCapitalizedAssetRetirementCosts	4774000	USD
CY2019	bkh	Non Cash Revision To Capitalized Asset Retirement Costs NonCashRevisionToCapitalizedAssetRetirementCosts	5044000	USD
CY2018	bkh	Non Cash Revision To Capitalized Asset Retirement Costs NonCashRevisionToCapitalizedAssetRetirementCosts	2625000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1820206000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	272662000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7027000	USD
CY2018	bkh	Tax Cutsand Jobs Actof2017 Reclassificationfrom Aoc Ito Retained Earnings TaxCutsandJobsActof2017ReclassificationfromAOCItoRetainedEarnings	740000	USD
CY2018	bkh	Reclassificationfrom Legal Entity Restructuring ReclassificationfromLegalEntityRestructuring	6519000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.93
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	106591000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	7190000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	299000000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	15000	USD
CY2018	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	220000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	-82000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	19617000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2287423000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	213322000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3739000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.05
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	124647000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	7076000	USD
CY2019	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	100000000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	1182000	USD
CY2019	us-gaap	Stockholders Equity Other StockholdersEquityOther	-327000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	17901000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2464069000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	242763000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3309000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.17
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	135439000	USD
CY2020	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5194000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	100000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Stock Issued Issuance Costs AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts	1203000	USD
CY2020	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	15839000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2662647000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:700;line-height:120%">Use of Estimates and Basis of Presentation</span></div><div><span><br/></span></div><div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of certain assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Changes in facts and circumstances or additional information may result in revised estimates and actual results could differ materially from those estimates.</span></div><div><span><br/></span></div><div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:700;line-height:120%">COVID-19 Pandemic</span></div><div><span><br/></span></div><div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">In March 2020, the World Health Organization categorized COVID-19 as a pandemic and the President of the United States declared the outbreak a national emergency. The U.S. government has deemed electric and natural gas utilities to be critical infrastructure sectors that provide essential services during this emergency. As a provider of essential services, the Company has an obligation to provide services to our customers. The Company remains focused on protecting the health of our customers, employees and the communities in which we operate while assuring the continuity of our business operations.</span></div><div><span><br/></span></div><div><span style="color:#000000;font-family:'Arial',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The Company’s Consolidated Financial Statements reflect estimates and assumptions made by management that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the Consolidated Financial Statements and reported amounts of revenue and expenses during the reporting periods presented. The Company considered the impacts of COVID-19 on the assumptions and estimates used and determined that, for the year ended December 31, 2020, there were no material adverse impacts on the Company’s results of operations.</span></div>
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	7003000	USD
CY2020Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	265961000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2444000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	255805000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2444000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	8927000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	4728000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	9096000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	7003000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	3209000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	5795000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	3942000	USD
CY2019	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	10502000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	2444000	USD
CY2017Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	3081000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	6859000	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	4092000	USD
CY2018	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	10823000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	3209000	USD
CY2020Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	85250000	USD
CY2019Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	82809000	USD
CY2020Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	1531000	USD
CY2019Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	2425000	USD
CY2020Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	30619000	USD
CY2019Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	31938000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	117400000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	117172000	USD
CY2019Q1	bkh	Assets Usedto Acquire Other Investments AssetsUsedtoAcquireOtherInvestments	28000000	USD
CY2019Q3	bkh	Discount Rate Usedin Valuationof Fair Valueof Oiland Gas Reserve Quantities DiscountRateUsedinValuationofFairValueofOilandGasReserveQuantities	0.10
CY2019Q3	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	20000000	USD
CY2019Q1	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	6900000	USD
CY2020Q4	us-gaap	Long Term Investments LongTermInvestments	15810000	USD
CY2019Q4	us-gaap	Long Term Investments LongTermInvestments	21929000	USD
CY2019Q4	bkh	Balance Sheet Reclassification From Investments To Other Assets Non Current BalanceSheetReclassificationFromInvestmentsToOtherAssetsNonCurrent	22000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	1299454000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	13266000	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	14337000	USD
CY2017Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	7559000	USD
CY2020	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	0	USD
CY2019	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	0	USD
CY2018	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	7602000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1322000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1071000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	824000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	11944000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	13266000	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	14337000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	1300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	1300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	1300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	1300000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	1300000	USD
CY2020Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	77806000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	62837000	USD
CY2020Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	47105000	USD
CY2019Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	44547000	USD
CY2020Q4	bkh	Customer Depositsand Prepayments CustomerDepositsandPrepayments	52185000	USD
CY2019Q4	bkh	Customer Depositsand Prepayments CustomerDepositsandPrepayments	54728000	USD
CY2020Q4	us-gaap	Interest Payable Current InterestPayableCurrent	31520000	USD
CY2019Q4	us-gaap	Interest Payable Current InterestPayableCurrent	31868000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	34996000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	32787000	USD
CY2020Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	243612000	USD
CY2019Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	226767000	USD
CY2020Q4	us-gaap	Regulatory Assets RegulatoryAssets	278000000	USD
CY2019Q4	us-gaap	Regulatory Assets RegulatoryAssets	271000000	USD
CY2020Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	533000000	USD
CY2019Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	537000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	227608000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	199310000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	258442000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	62378000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	60662000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	54420000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Equity Unit Purchase Agreements IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements	0	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Equity Unit Purchase Agreements IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements	0	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Equity Unit Purchase Agreements IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements	898000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	61000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	136000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	168000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	62439000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	60798000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	55486000	shares
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.65
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.28
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.66
CY2020	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	60000	shares
CY2019	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1000	shares
CY2018	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	16000	shares
CY2020Q4	us-gaap	Regulatory Assets RegulatoryAssets	278258000	USD
CY2019Q4	us-gaap	Regulatory Assets RegulatoryAssets	271344000	USD
CY2020Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	51676000	USD
CY2019Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	43282000	USD
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	226582000	USD
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	228062000	USD
CY2020Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	532720000	USD
CY2019Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	536652000	USD
CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	25061000	USD
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	33507000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	507659000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	503145000	USD
CY2020	bkh	Benefit From Relieved Tcja Related Liabilities BenefitFromRelievedTCJARelatedLiabilities	4000000.0	USD
CY2019Q1	bkh	Public Utilities Numberof Gas Distribution Territories Consolidating PublicUtilitiesNumberofGasDistributionTerritoriesConsolidating	2	gas_distribution_territory
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1680804000	USD
CY2020	us-gaap	Revenues Revenues	1696941000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1680804000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1726392000	USD
CY2019	us-gaap	Revenues Revenues	1734900000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1726392000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1748542000	USD
CY2018	us-gaap	Revenues Revenues	1754268000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1748542000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	64205000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	5999000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	317000	USD
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	2769000	USD
CY2020	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	-1225000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	71431000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	56800000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	3445000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	380000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	2741000	USD
CY2019	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	1599000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	64205000	USD
CY2020Q4	bkh	Number Of Finance Leases NumberOfFinanceLeases	1	lease
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0424
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	4188000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	4629000	USD
CY2020Q4	bkh	Lease Liability LeaseLiability	4543000	USD
CY2019Q4	bkh	Lease Liability LeaseLiability	5000000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	1023000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	1263000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	161000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	2801000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0424
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0427
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	907000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	804000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	779000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	776000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	529000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1643000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	5438000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	895000	USD
CY2020Q4	bkh	Lease Liability LeaseLiability	4543000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	2534000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	2306000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Next Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths	2383000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	2122000	USD
CY2020Q4	bkh	Long Term Debt Before The Deduction Of Deferred Financing Costs LongTermDebtBeforeTheDeductionOfDeferredFinancingCosts	3561345000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	2130000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	2074000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	2090000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Thereafter LessorOperatingLeasePaymentsToBeReceivedThereafter	58829000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	69628000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	234040000	USD
CY2020Q4	us-gaap	Letters Of Credit Outstanding Amount LettersOfCreditOutstandingAmount	24730000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	349500000	USD
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CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-1180000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-23667000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	279549000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-6887000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	272662000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	14220000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	258442000	USD

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$BKH
BLACK HILLS CORP /SD/ Stock $bkh

2019 Q4 Form 10-K Financial Statement

#000113046421000007 Filed on February 26, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKH BLACK HILLS CORP /SD/ Stock $bkh

2019 Q4 Form 10-K Financial Statement

#000113046421000007 Filed on February 26, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKH
BLACK HILLS CORP /SD/ Stock $bkh