$BKH
BLACK HILLS CORP /SD/ Stock $bkh

$bkh Overview Financials Valuation SEC Filings Company Website

2013 Form 10-K Financial Statement

#000113046414000056 Filed on February 26, 2014

Income Statement

Concept	2013	2012 Q4	2012 Q3
Revenue	$1.276B	$318.9M	$246.8M
YoY Change	8.69%	-11.72%	-1.09%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$137.3M	$33.20M	$41.41M
YoY Change	-11.19%	-13.09%	24.43%
% of Gross Profit
Operating Expenses	$1.016B	$245.4M	$169.0M
YoY Change	9.27%	-20.58%	-19.51%
Operating Profit	$259.4M	$75.26M	$77.81M
YoY Change	6.46%	44.35%	96.63%
Interest Expense	$111.8M	-$26.20M	-$25.20M
YoY Change	-1.6%	12.93%	-58.35%
% of Operating Profit	43.09%	-34.81%	-32.39%
Other Income/Expense, Net	$1.798M	$200.0K	-$287.0K
YoY Change	2432.39%	0.0%	-154.36%
Pretax Income	$181.4M	$49.30M	$52.52M
YoY Change	32.53%	69.42%	-359.68%
Income Tax	$63.04M	$18.30M	$17.91M
% Of Pretax Income	34.75%	37.12%	34.11%
Net Earnings	$115.0M	$30.77M	$34.46M
YoY Change	41.01%	20.22%	-427.38%
Net Earnings / Revenue	9.01%	9.65%	13.96%
Basic Earnings Per Share	$2.66	$0.70	$0.79
Diluted Earnings Per Share	$2.64	$0.70	$0.78
COMMON SHARES
Basic Shares Outstanding	44.16M shares	44.18M shares	43.85M shares
Diluted Shares Outstanding	44.42M shares		44.11M shares

Balance Sheet

Concept	2013	2012 Q4	2012 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$7.800M	$15.50M	$247.2M
YoY Change	-49.68%	-28.24%	718.54%
Cash & Equivalents	$7.800M	$15.46M	$247.2M
Short-Term Investments
Other Short-Term Assets	$69.90M	$28.80M	$44.82M
YoY Change	-52.87%	35.4%	77.38%
Inventory	$88.50M	$77.64M	$80.90M
Prepaid Expenses
Receivables	$177.6M	$163.7M	$104.5M
Other Receivables	$1.400M	$0.00	$11.90M
Total Short-Term Assets	$345.3M	$405.1M	$570.9M
YoY Change	-14.76%	-46.62%	-16.03%
LONG-TERM ASSETS
Property, Plant & Equipment	$2.953B	$2.743B	$2.696B
YoY Change	7.67%	-1.68%	-1.07%
Goodwill		$353.4M	$353.4M
YoY Change		0.0%	0.0%
Intangibles		$3.620M	$3.675M
YoY Change		-5.8%	-5.75%
Long-Term Investments	$16.70M	$16.40M	$16.30M
YoY Change	1.83%	-5.2%	-5.78%
Other Assets	$166.1M	$19.42M	$19.85M
YoY Change	-20.22%	-2.61%	-1.15%
Total Long-Term Assets	$3.493B	$565.2M	$570.0M
YoY Change	5.06%	0.69%	9.01%
TOTAL ASSETS
Total Short-Term Assets	$345.3M	$405.1M	$570.9M
Total Long-Term Assets	$3.493B	$565.2M	$570.0M
Total Assets	$3.838B	$3.729B	$3.854B
YoY Change	2.91%	-9.63%	-2.33%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$130.4M	$84.42M	$69.14M
YoY Change	54.5%	-19.4%	-24.54%
Accrued Expenses	$151.3M	$154.4M	$179.3M
YoY Change	-2.01%	2.03%	10.91%
Deferred Revenue
YoY Change
Short-Term Debt	$82.50M	$277.0M	$225.0M
YoY Change	-70.22%	-19.71%	-37.33%
Long-Term Debt Due	$0.00	$104.0M	$328.3M
YoY Change	-100.0%	4104.33%	11248.43%
Total Short-Term Liabilities	$378.4M	$734.9M	$898.9M
YoY Change	-48.51%	-16.31%	0.02%
LONG-TERM LIABILITIES
Long-Term Debt	$1.397B	$938.9M	$943.0M
YoY Change	48.78%	-26.67%	-26.46%
Other Long-Term Liabilities	$779.1M	$125.3M	$129.6M
YoY Change	-5.36%	1.41%	2.07%
Total Long-Term Liabilities	$2.176B	$823.2M	$797.4M
YoY Change	23.49%	8.42%	17.85%
TOTAL LIABILITIES
Total Short-Term Liabilities	$378.4M	$734.9M	$898.9M
Total Long-Term Liabilities	$2.176B	$823.2M	$797.4M
Total Liabilities	$2.554B	$1.558B	$1.696B
YoY Change	2.3%	-4.84%	7.68%
SHAREHOLDERS EQUITY
Retained Earnings		$492.9M	$478.5M
YoY Change		3.41%	2.44%
Common Stock		$777.4M	$775.4M
YoY Change		1668.44%	1863.5%
Preferred Stock
YoY Change
Treasury Stock (at cost)		$2.245M	$2.354M
YoY Change		131.44%	190.62%
Treasury Stock Shares		71.78K shares	75.42K shares
Shareholders Equity	$1.284B	$1.206B	$1.214B
YoY Change
Total Liabilities & Shareholders Equity	$3.838B	$3.729B	$3.854B
YoY Change	2.91%	-9.63%	-2.33%

Cashflow Statement

Concept	2013	2012 Q4	2012 Q3
OPERATING ACTIVITIES
Net Income	$115.0M	$30.77M	$34.46M
YoY Change	41.01%	20.22%	-427.38%
Depreciation, Depletion And Amortization	$137.3M	$33.20M	$41.41M
YoY Change	-11.19%	-13.09%	24.43%
Cash From Operating Activities	$324.6M	$47.30M	$93.00M
YoY Change	2.42%	175.0%	279.59%
INVESTING ACTIVITIES
Capital Expenditures	$354.7M	-$87.70M	-$112.6M
YoY Change	1.61%	-23.2%	9.32%
Acquisitions
YoY Change
Other Investing Activities	-$5.471M	$600.0K	$247.6M
YoY Change	-3139.44%	-110.0%	18946.15%
Cash From Investing Activities	-$349.3M	-$87.10M	$135.0M
YoY Change	-3227.21%	-27.48%	-232.61%
FINANCING ACTIVITIES
Cash Dividend Paid	$67.59M
YoY Change	3.56%
Common Stock Issuance & Retirement, Net	$4.354M
YoY Change	-7.87%
Debt Paid & Issued, Net	$445.9M
YoY Change	85.73%
Cash From Financing Activities	$17.03M	-191.9M	-20.80M
YoY Change	-104.58%	-320.83%	-132.5%
NET CHANGE
Cash From Operating Activities	$324.6M	47.30M	93.00M
Cash From Investing Activities	-$349.3M	-87.10M	135.0M
Cash From Financing Activities	$17.03M	-191.9M	-20.80M
Net Change In Cash	-$7.621M	-231.7M	207.2M
YoY Change	-82.4%	1348.12%	-1657.89%
FREE CASH FLOW
Cash From Operating Activities	$324.6M	$47.30M	$93.00M
Capital Expenditures	$354.7M	-$87.70M	-$112.6M
Free Cash Flow	-$30.12M	$135.0M	$205.6M
YoY Change	-6.34%	2.74%	61.25%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2013Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	130416000	USD
CY2012Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	84422000	USD
CY2012Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	163698000	USD
CY2013Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	177573000	USD
CY2011	us-gaap	Accretion Of Discount AccretionOfDiscount	19655000	USD
CY2012	us-gaap	Accretion Of Discount AccretionOfDiscount	25509000	USD
CY2013	us-gaap	Accretion Of Discount AccretionOfDiscount	15126000	USD
CY2012Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	4936000	USD
CY2013Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	0	USD
CY2013Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	151277000	USD
CY2012Q4	us-gaap	Accrued Liabilities Current AccruedLiabilitiesCurrent	154389000	USD
CY2013Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1269148000	USD
CY2012Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	1188023000	USD
CY2013Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-17422000	USD
CY2012Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-35488000	USD
CY2011Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-32878000	USD
CY2013	us-gaap	Acquisition Costs AcquisitionCosts	57631000	USD
CY2013Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	742344000	USD
CY2012Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	733095000	USD
CY2013	us-gaap	Adjustments To Additional Paid In Capital Tax Effect From Share Based Compensation AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation	410000	USD
CY2012	us-gaap	Adjustments To Additional Paid In Capital Tax Effect From Share Based Compensation AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation	117000	USD
CY2011	us-gaap	Adjustments To Additional Paid In Capital Tax Effect From Share Based Compensation AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation	-28000	USD
CY2013Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1237000	USD
CY2012Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	768000	USD
CY2012	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	5555000	USD
CY2013	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	6763000	USD
CY2011	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	5655000	USD
CY2012	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	223000	USD
CY2011	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	226000	USD
CY2013	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	223000	USD
CY2013	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	22000	shares
CY2011	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	141000	shares
CY2012	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	163000	shares
CY2012Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	50548000	USD
CY2011Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	42914000	USD
CY2013Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	51851000	USD
CY2012	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	2568000	USD
CY2013	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	2685000	USD
CY2012	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	5411000	USD
CY2013	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	146000	USD
CY2012	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	1081000	USD
CY2013	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	2617000	USD
CY2012	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	736000	USD
CY2013	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	1089000	USD
CY2013Q4	us-gaap	Assets Assets	3875178000	USD
CY2012Q4	us-gaap	Assets Assets	3729471000	USD
CY2013Q4	us-gaap	Assets Current AssetsCurrent	345288000	USD
CY2012Q4	us-gaap	Assets Current AssetsCurrent	405106000	USD
CY2012Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	565214000	USD
CY2013Q4	us-gaap	Assets Noncurrent AssetsNoncurrent	522896000	USD
CY2012	us-gaap	Business Exit Costs1 BusinessExitCosts1	2500000	USD
CY2011	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	37529000	USD
CY2012	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	35556000	USD
CY2013	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	59811000	USD
CY2011Q4	us-gaap	Capitalized Costs Accumulated Depreciation Depletion Amortization And Valuation Allowance For Relating To Oil And Gas Producing Activities CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities	361173000	USD
CY2012Q4	us-gaap	Capitalized Costs Accumulated Depreciation Depletion Amortization And Valuation Allowance For Relating To Oil And Gas Producing Activities CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities	534777000	USD
CY2013Q4	us-gaap	Capitalized Costs Accumulated Depreciation Depletion Amortization And Valuation Allowance For Relating To Oil And Gas Producing Activities CapitalizedCostsAccumulatedDepreciationDepletionAmortizationAndValuationAllowanceForRelatingToOilAndGasProducingActivities	555263000	USD
CY2013	us-gaap	Capitalized Costs Of Unproved Properties Excluded From Amortization CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortization	73483000	USD
CY2011Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Gross CapitalizedCostsOilAndGasProducingActivitiesGross	703150000	USD
CY2012Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Gross CapitalizedCostsOilAndGasProducingActivitiesGross	721970000	USD
CY2013Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Gross CapitalizedCostsOilAndGasProducingActivitiesGross	787898000	USD
CY2013Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Net CapitalizedCostsOilAndGasProducingActivitiesNet	232635000	USD
CY2012Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Net CapitalizedCostsOilAndGasProducingActivitiesNet	187193000	USD
CY2011Q4	us-gaap	Capitalized Costs Oil And Gas Producing Activities Net CapitalizedCostsOilAndGasProducingActivitiesNet	341977000	USD
CY2012Q4	us-gaap	Capitalized Costs Proved Properties CapitalizedCostsProvedProperties	662444000	USD
CY2011Q4	us-gaap	Capitalized Costs Proved Properties CapitalizedCostsProvedProperties	674494000	USD
CY2013Q4	us-gaap	Capitalized Costs Proved Properties CapitalizedCostsProvedProperties	725345000	USD
CY2013Q4	us-gaap	Capitalized Costs Unproved Properties CapitalizedCostsUnprovedProperties	62553000	USD
CY2012Q4	us-gaap	Capitalized Costs Unproved Properties CapitalizedCostsUnprovedProperties	59526000	USD
CY2011Q4	us-gaap	Capitalized Costs Unproved Properties CapitalizedCostsUnprovedProperties	28656000	USD
CY2013Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	7841000	USD
CY2012Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	15462000	USD
CY2010Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	32438000	USD
CY2012Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	15462000	USD
CY2011Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	58768000	USD
CY2013Q4	us-gaap	Cash And Cash Equivalents At Carrying Value Including Discontinued Operations CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	7841000	USD
CY2011	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	26330000	USD
CY2013	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-7621000	USD
CY2012	us-gaap	Cash And Cash Equivalents Period Increase Decrease CashAndCashEquivalentsPeriodIncreaseDecrease	-43306000	USD
CY2011	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	-158000	USD
CY2012	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	0	USD
CY2013	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	0	USD
CY2012	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-824000	USD
CY2011	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-2359000	USD
CY2013	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	0	USD
CY2012	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	21184000	USD
CY2011	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	7010000	USD
CY2013	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	-884000	USD
CY2013	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.52
CY2012	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.48
CY2011	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.46
CY2012Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.370
CY2012Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.370
CY2012Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.370
CY2012Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.370
CY2013Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.380
CY2013Q1	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.380
CY2013Q2	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.380
CY2013Q4	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.380
CY2012Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
CY2013Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	1.00
CY2013Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2012Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	100000000	shares
CY2012Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	44278189	shares
CY2013Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	44550239	shares
CY2013Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	44499362	shares
CY2012Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	44206408	shares
CY2012Q4	us-gaap	Common Stock Value CommonStockValue	44278000	USD
CY2013Q4	us-gaap	Common Stock Value CommonStockValue	44550000	USD
CY2011	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	40433000	USD
CY2013	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	133028000	USD
CY2012	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	78918000	USD
CY2011	us-gaap	Costs And Expenses CostsAndExpenses	375369000	USD
CY2012	us-gaap	Costs And Expenses CostsAndExpenses	370736000	USD
CY2013	us-gaap	Costs And Expenses CostsAndExpenses	386936000	USD
CY2011	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-14539000	USD
CY2013	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-2003000	USD
CY2012	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	4972000	USD
CY2013	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-2176000	USD
CY2011	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-15376000	USD
CY2012	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	8684000	USD
CY2011	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-837000	USD
CY2012	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	3712000	USD
CY2013	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-173000	USD
CY2013	us-gaap	Decrease Due To Sales Of Minerals In Place DecreaseDueToSalesOfMineralsInPlace	869000	USD
CY2012	us-gaap	Decrease Due To Sales Of Minerals In Place DecreaseDueToSalesOfMineralsInPlace	37175000	USD
CY2011	us-gaap	Decrease Due To Sales Of Minerals In Place DecreaseDueToSalesOfMineralsInPlace	1013000	USD
CY2011	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	30876000	USD
CY2013	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	56963000	USD
CY2012	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	39876000	USD
CY2012	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	39716000	USD
CY2011	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	33600000	USD
CY2013	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	63784000	USD
CY2012Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	694880000	USD
CY2013Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	753785000	USD
CY2012	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	68000	USD
CY2011	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2970000	USD
CY2013	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	7033000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	35947000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	1594000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	386203000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	340387000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	18889000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Net Current DeferredTaxAssetsNetCurrent	77231000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	166095000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards DeferredTaxAssetsOperatingLossCarryforwards	147153000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	32803000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	36502000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	20038000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Other Comprehensive Loss DeferredTaxAssetsOtherComprehensiveLoss	9733000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	33172000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Regulatory Assets And Liabilities DeferredTaxAssetsRegulatoryAssetsAndLiabilities	57471000	USD
CY2013Q4	us-gaap	Deferred Tax Assets State Taxes DeferredTaxAssetsStateTaxes	14948000	USD
CY2012Q4	us-gaap	Deferred Tax Assets State Taxes DeferredTaxAssetsStateTaxes	15546000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	23767000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits	28724000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Impairment Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsImpairmentLosses	55124000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Impairment Losses DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsImpairmentLosses	55971000	USD
CY2012Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	6192000	USD
CY2013Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	1806000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	308677000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	413398000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	15593000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Deferred Expense DeferredTaxLiabilitiesDeferredExpense	17723000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	385908000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Noncurrent DeferredTaxLiabilitiesNoncurrent	432287000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	15104000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	13961000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	571262000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Property Plant And Equipment DeferredTaxLiabilitiesPropertyPlantAndEquipment	598415000	USD
CY2013Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssets	24581000	USD
CY2012Q4	us-gaap	Deferred Tax Liabilities Regulatory Assets DeferredTaxLiabilitiesRegulatoryAssets	23537000	USD
CY2013	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets	0.0725
CY2012	us-gaap	Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets	0.0725
CY2013	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Accumulated Postretirement Benefit Obligation1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1	1644000	USD
CY2013	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Service And Interest Cost Components1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1	116000	USD
CY2013	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Accumulated Postretirement Benefit Obligation DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation	1914000	USD
CY2013	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Service And Interest Cost Components DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents	136000	USD
CY2013	us-gaap	Defined Benefit Plan Measurement Date DefinedBenefitPlanMeasurementDate	December 31
CY2013	us-gaap	Defined Benefit Plan Target Plan Asset Allocations DefinedBenefitPlanTargetPlanAssetAllocations	1
CY2012	us-gaap	Defined Benefit Plan Target Plan Asset Allocations DefinedBenefitPlanTargetPlanAssetAllocations	1
CY2013	us-gaap	Defined Benefit Plans Estimated Future Employer Contributions In Next Fiscal Year DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear	0	USD
CY2013	us-gaap	Defined Contribution Plan Maximum Annual Contributions Per Employee Percent DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent	0.50
CY2013	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	141217000	USD
CY2011	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	135591000	USD
CY2012	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	154632000	USD
CY2012Q4	us-gaap	Derivative Assets DerivativeAssets	3746000	USD
CY2013Q4	us-gaap	Derivative Assets DerivativeAssets	717000	USD
CY2013Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	717000	USD
CY2012Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	3236000	USD
CY2013Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	0	USD
CY2012Q4	us-gaap	Derivative Assets Noncurrent DerivativeAssetsNoncurrent	510000	USD
CY2012Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	0	USD
CY2013Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	0	USD
CY2013Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	5021000	USD
CY2012Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	6141000	USD
CY2012Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	5332000	USD
CY2013Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	3975000	USD
CY2012Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	129424000	USD
CY2013Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	19948000	USD
CY2011	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-55383000	USD
CY2013	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	17267000	USD
CY2012	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-11077000	USD
CY2012Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	113482000	USD
CY2013Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	9088000	USD
CY2012Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	96541000	USD
CY2013Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	3474000	USD
CY2013Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	5614000	USD
CY2012Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	16941000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves10 Percent Annual Discount For Estimated Timing Of Cash Flows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows	107375000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves10 Percent Annual Discount For Estimated Timing Of Cash Flows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows	101632000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves10 Percent Annual Discount For Estimated Timing Of Cash Flows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves10PercentAnnualDiscountForEstimatedTimingOfCashFlows	197215000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Cash Inflows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows	931637000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Cash Inflows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows	602501000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Cash Inflows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureCashInflows	502769000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Development Costs1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1	-40557000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Development Costs1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1	-92233000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Development Costs1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureDevelopmentCosts1	-8462000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Income Tax Expense1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1	-69877000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Income Tax Expense1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1	-157922000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Income Tax Expense1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureIncomeTaxExpense1	-81566000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Net Cash Flows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows	400572000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Net Cash Flows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows	266800000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Net Cash Flows DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureNetCashFlows	237735000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Production Costs1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1	-186695000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Production Costs1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1	-213578000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Future Production Costs1 DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesFutureProductionCosts1	-280910000	USD
CY2013	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Standardized Measure DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure	159425000	USD
CY2011	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Standardized Measure DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure	203357000	USD
CY2012	us-gaap	Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves Standardized Measure DiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReservesStandardizedMeasure	136103000	USD
CY2011Q4	us-gaap	Disposal Group Including Discontinued Operation Cash And Cash Equivalents DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents	37000000	USD
CY2010Q4	us-gaap	Disposal Group Including Discontinued Operation Cash And Cash Equivalents DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents	16000000	USD
CY2012	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	65262000	USD
CY2013	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	67587000	USD
CY2011	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	59202000	USD
CY2013	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.60
CY2012	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.86
CY2011	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.25
CY2012Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.70
CY2012Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.68
CY2012Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.31
CY2012Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.79
CY2013Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.69
CY2013Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.41
CY2013Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.52
CY2013Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.98
CY2012	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.85
CY2011	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.24
CY2013	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.59
CY2012Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.78
CY2012Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2012Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.31
CY2012Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.68
CY2013Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.41
CY2013Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.97
CY2013Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.52
CY2013Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.69
CY2012	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.354
CY2013	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.347
CY2011	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.311
CY2011	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2012	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2013	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depletion EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepletion	-0.025
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depletion EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepletion	-0.010
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depletion EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepletion	-0.013
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.009
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.005
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.004
CY2012	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.020
CY2011	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.018
CY2013	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.024
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies	0.008
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies	0.007
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies EffectiveIncomeTaxRateReconciliationTaxContingencies	0.028
CY2012	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.000
CY2011	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	0.000
CY2013	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits EffectiveIncomeTaxRateReconciliationTaxCredits	-0.005
CY2013Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	9900000	USD
CY2013	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P1Y8M
CY2012Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	25657000	USD
CY2013Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	32069000	USD
CY2013Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	6213000	USD
CY2012Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	8589000	USD
CY2013	us-gaap	Exploration Costs ExplorationCosts	10930000	USD
CY2012	us-gaap	Extensions Discoveries Additions And Improved Recovery Less Related Costs ExtensionsDiscoveriesAdditionsAndImprovedRecoveryLessRelatedCosts	19870000	USD
CY2011	us-gaap	Extensions Discoveries Additions And Improved Recovery Less Related Costs ExtensionsDiscoveriesAdditionsAndImprovedRecoveryLessRelatedCosts	31179000	USD
CY2013	us-gaap	Extensions Discoveries Additions And Improved Recovery Less Related Costs ExtensionsDiscoveriesAdditionsAndImprovedRecoveryLessRelatedCosts	29574000	USD
CY2013Q4	us-gaap	Fair Value Assets Level1 To Level2 Transfers Amount FairValueAssetsLevel1ToLevel2TransfersAmount	0	USD
CY2012Q4	us-gaap	Fair Value Assets Level1 To Level2 Transfers Amount FairValueAssetsLevel1ToLevel2TransfersAmount	0	USD
CY2013Q4	us-gaap	Fair Value Assets Level2 To Level1 Transfers Amount FairValueAssetsLevel2ToLevel1TransfersAmount	0	USD
CY2012Q4	us-gaap	Fair Value Assets Level2 To Level1 Transfers Amount FairValueAssetsLevel2ToLevel1TransfersAmount	0	USD
CY2013Q4	us-gaap	Fair Value Liabilities Level1 To Level2 Transfers Amount FairValueLiabilitiesLevel1ToLevel2TransfersAmount	0	USD
CY2012Q4	us-gaap	Fair Value Liabilities Level1 To Level2 Transfers Amount FairValueLiabilitiesLevel1ToLevel2TransfersAmount	0	USD
CY2013Q4	us-gaap	Fair Value Liabilities Level2 To Level1 Transfers Amount FairValueLiabilitiesLevel2ToLevel1TransfersAmount	0	USD
CY2012Q4	us-gaap	Fair Value Liabilities Level2 To Level1 Transfers Amount FairValueLiabilitiesLevel2ToLevel1TransfersAmount	0	USD
CY2013	us-gaap	Finite Lived Intangible Asset Useful Life FiniteLivedIntangibleAssetUsefulLife	P20Y
CY2013Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	200000	USD
CY2013Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	200000	USD
CY2013Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	200000	USD
CY2013Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	200000	USD
CY2013Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	200000	USD
CY2012	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	29129000	USD
CY2011	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2013	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	0	USD
CY2012Q3	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	27000000	USD
CY2012Q4	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	1800000	USD
CY2013Q4	us-gaap	Gas And Oil Area Undeveloped Net GasAndOilAreaUndevelopedNet	235517	acre
CY2012Q4	us-gaap	Goodwill Goodwill	353396000	USD
CY2013Q4	us-gaap	Goodwill Goodwill	353396000	USD
CY2011Q4	us-gaap	Goodwill Goodwill	353396000	USD
CY2013	us-gaap	Goodwill Other Changes GoodwillOtherChanges	0	USD
CY2012	us-gaap	Goodwill Other Changes GoodwillOtherChanges	0	USD
CY2013Q4	us-gaap	Guarantee Obligations Maximum Exposure GuaranteeObligationsMaximumExposure	134449000	USD
CY2012	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	26868000	USD
CY2011	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	0	USD
CY2013	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	0	USD
CY2012Q2	us-gaap	Impairment Of Oil And Gas Properties ImpairmentOfOilAndGasProperties	27000000	USD
CY2013	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	115846000	USD
CY2012	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	88505000	USD
CY2011	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	40365000	USD
CY2012Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	35271000	USD
CY2012Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	30934000	USD
CY2012Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-12323000	USD
CY2012Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	34623000	USD
CY2013Q4	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	19007000	USD
CY2013Q3	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	23124000	USD
CY2013Q1	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	43197000	USD
CY2013Q2	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	30518000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	177540000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	136895000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	57468000	USD
CY2012	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	88505000	USD
CY2011	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	40365000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	115846000	USD
CY2013	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.62
CY2012	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	2.02
CY2011	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.01
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.79
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.70
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	-0.28
CY2012Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.81
CY2013Q2	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.69
CY2013Q1	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.98
CY2013Q4	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.43
CY2013Q3	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	0.52
CY2011	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.01
CY2013	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.61
CY2012	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	2.01
CY2012Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	-0.28
CY2012Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.78
CY2012Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.70
CY2012Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.80
CY2013Q1	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.97
CY2013Q3	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.52
CY2013Q4	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.43
CY2013Q2	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	0.69
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-6977000	USD
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	9365000	USD
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax IncomeLossFromDiscontinuedOperationsNetOfTax	-884000	USD
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-167000	USD
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-1160000	USD
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-166000	USD
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-5484000	USD
CY2013Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-884000	USD
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.02
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.24
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.16
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.00
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.00
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.13
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.03
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.00
CY2013Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	-0.02
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.00
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Basic Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare	0.00
CY2013	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.02
CY2011	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.23
CY2012	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.16
CY2012Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2012Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2012Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.03
CY2012Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.12
CY2013Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2013Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	-0.02
CY2013Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2013Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Per Diluted Share IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare	0.00
CY2013	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-86000	USD
CY2012	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	10000	USD
CY2011	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	1121000	USD
CY2013	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	61608000	USD
CY2012	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	48400000	USD
CY2011	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	18224000	USD
CY2011	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-9854000	USD
CY2013	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	4573000	USD
CY2012	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	3027000	USD
CY2012Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	0	USD
CY2013Q4	us-gaap	Income Taxes Receivable IncomeTaxesReceivable	1460000	USD
CY2013	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	13921000	USD
CY2011	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-22290000	USD
CY2012	us-gaap	Increase Decrease In Accounts Receivable And Other Operating Assets IncreaseDecreaseInAccountsReceivableAndOtherOperatingAssets	-13739000	USD
CY2011	us-gaap	Increase Decrease In Estimated Future Development Costs IncreaseDecreaseInEstimatedFutureDevelopmentCosts	43809000	USD
CY2013	us-gaap	Increase Decrease In Estimated Future Development Costs IncreaseDecreaseInEstimatedFutureDevelopmentCosts	-12216000	USD
CY2012	us-gaap	Increase Decrease In Estimated Future Development Costs IncreaseDecreaseInEstimatedFutureDevelopmentCosts	43854000	USD
CY2012	us-gaap	Increase Decrease In Future Income Tax Expense Estimates On Future Cash Flows Related To Proved Oil And Gas Reserves IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves	36578000	USD
CY2011	us-gaap	Increase Decrease In Future Income Tax Expense Estimates On Future Cash Flows Related To Proved Oil And Gas Reserves IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves	-23283000	USD
CY2013	us-gaap	Increase Decrease In Future Income Tax Expense Estimates On Future Cash Flows Related To Proved Oil And Gas Reserves IncreaseDecreaseInFutureIncomeTaxExpenseEstimatesOnFutureCashFlowsRelatedToProvedOilAndGasReserves	-3892000	USD
CY2013	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	5770000	USD
CY2012	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-6343000	USD
CY2011	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	21385000	USD
CY2011	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-31091000	USD
CY2012	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	-10713000	USD
CY2013	us-gaap	Increase Decrease In Other Accounts Payable And Accrued Liabilities IncreaseDecreaseInOtherAccountsPayableAndAccruedLiabilities	15336000	USD
CY2012	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	6670000	USD
CY2011	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	13721000	USD
CY2013	us-gaap	Increase Decrease In Other Operating Capital Net IncreaseDecreaseInOtherOperatingCapitalNet	-312000	USD
CY2012	us-gaap	Increase Due To Purchases Of Minerals In Place IncreaseDueToPurchasesOfMineralsInPlace	0	USD
CY2013	us-gaap	Increase Due To Purchases Of Minerals In Place IncreaseDueToPurchasesOfMineralsInPlace	0	USD
CY2011	us-gaap	Increase Due To Purchases Of Minerals In Place IncreaseDueToPurchasesOfMineralsInPlace	0	USD
CY2013	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	256000	shares
CY2011	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	214000	shares
CY2012	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	250000	shares
CY2013Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	3397000	USD
CY2012Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	3620000	USD
CY2011Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	3843000	USD
CY2010Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	4069000	USD
CY2012	us-gaap	Interest Costs Incurred InterestCostsIncurred	117754000	USD
CY2013	us-gaap	Interest Costs Incurred InterestCostsIncurred	113979000	USD
CY2011	us-gaap	Interest Costs Incurred InterestCostsIncurred	116684000	USD
CY2011	us-gaap	Interest Expense InterestExpense	91383000	USD
CY2012	us-gaap	Interest Expense InterestExpense	113610000	USD
CY2013	us-gaap	Interest Expense InterestExpense	111788000	USD
CY2012	us-gaap	Interest Paid Net InterestPaidNet	116593000	USD
CY2013	us-gaap	Interest Paid Net InterestPaidNet	108361000	USD
CY2011	us-gaap	Interest Paid Net InterestPaidNet	103110000	USD
CY2012Q4	us-gaap	Inventory Net InventoryNet	77643000	USD
CY2013Q4	us-gaap	Inventory Net InventoryNet	88478000	USD
CY2012Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	43397000	USD
CY2013Q4	us-gaap	Inventory Raw Materials And Supplies InventoryRawMaterialsAndSupplies	50196000	USD
CY2011	us-gaap	Investment Income Interest InvestmentIncomeInterest	2017000	USD
CY2012	us-gaap	Investment Income Interest InvestmentIncomeInterest	1957000	USD
CY2013	us-gaap	Investment Income Interest InvestmentIncomeInterest	1723000	USD
CY2013	us-gaap	Investment Tax Credit InvestmentTaxCredit	-212000	USD
CY2012	us-gaap	Investment Tax Credit InvestmentTaxCredit	-228000	USD
CY2011	us-gaap	Investment Tax Credit InvestmentTaxCredit	-246000	USD
CY2011	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	6125000	USD
CY2012	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	6839000	USD
CY2013	us-gaap	Lease And Rental Expense LeaseAndRentalExpense	7169000	USD
CY2013Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3875178000	USD
CY2012Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	3729471000	USD
CY2013Q4	us-gaap	Liabilities Current LiabilitiesCurrent	378394000	USD
CY2012Q4	us-gaap	Liabilities Current LiabilitiesCurrent	734889000	USD
CY2013Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	792088000	USD
CY2012Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	823196000	USD
CY2011Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	49327000	USD
CY2012Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	40683000	USD
CY2013Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	37631000	USD
CY2010Q4	us-gaap	Liability For Uncertain Tax Positions Noncurrent LiabilityForUncertainTaxPositionsNoncurrent	50135000	USD
CY2013	us-gaap	Long Term Contract For Purchase Of Electric Power Date Of Contract Expiration LongTermContractForPurchaseOfElectricPowerDateOfContractExpiration	2037-10-16
CY2013Q4	us-gaap	Long Term Debt LongTermDebt	1396948000	USD
CY2012Q4	us-gaap	Long Term Debt LongTermDebt	1042850000	USD
CY2012Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	103973000	USD
CY2013Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	0	USD
CY2013Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1122055000	USD
CY2013Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	0	USD
CY2013Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	0	USD
CY2013Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	0	USD
CY2013Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	275000000	USD
CY2012Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	938877000	USD
CY2013Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1396948000	USD
CY2012Q4	us-gaap	Long Term Investments LongTermInvestments	16402000	USD
CY2013Q4	us-gaap	Long Term Investments LongTermInvestments	16697000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-371446000	USD
CY2013	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	17028000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	249633000	USD
CY2012	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-371446000	USD
CY2011	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	249791000	USD
CY2013	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	17028000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-447007000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	11169000	USD
CY2013	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-349278000	USD
CY2011	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-444648000	USD
CY2013	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-349278000	USD
CY2012	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-95518000	USD
CY2013	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	324629000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	223704000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	316971000	USD
CY2012	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	295787000	USD
CY2013	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	325513000	USD
CY2011	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	216694000	USD
CY2011	us-gaap	Net Income Loss NetIncomeLoss	49730000	USD
CY2013	us-gaap	Net Income Loss NetIncomeLoss	114962000	USD
CY2012	us-gaap	Net Income Loss NetIncomeLoss	81528000	USD
CY2013	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	114962000	USD
CY2012	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	81528000	USD
CY2011	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	49730000	USD
CY2012Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-13483000	USD
CY2012Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	34457000	USD
CY2012Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	30767000	USD
CY2012Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	29787000	USD
CY2013Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	30518000	USD
CY2013Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	23124000	USD
CY2013Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	18123000	USD
CY2013Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	43197000	USD
CY2013	us-gaap	Net Increase Decrease In Sales And Transfer Prices And Production Costs NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts	15126000	USD
CY2011	us-gaap	Net Increase Decrease In Sales And Transfer Prices And Production Costs NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts	57087000	USD
CY2012	us-gaap	Net Increase Decrease In Sales And Transfer Prices And Production Costs NetIncreaseDecreaseInSalesAndTransferPricesAndProductionCosts	-42639000	USD
CY2011	us-gaap	Operating Expenses OperatingExpenses	1085949000	USD
CY2012	us-gaap	Operating Expenses OperatingExpenses	930173000	USD
CY2013	us-gaap	Operating Expenses OperatingExpenses	1020300000	USD
CY2011	us-gaap	Operating Income Loss OperatingIncomeLoss	186239000	USD
CY2013	us-gaap	Operating Income Loss OperatingIncomeLoss	255552000	USD
CY2012	us-gaap	Operating Income Loss OperatingIncomeLoss	243711000	USD
CY2012Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	77810000	USD
CY2012Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	20591000	USD
CY2012Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	75262000	USD
CY2012Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	70048000	USD
CY2013Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	71103000	USD
CY2013Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	79846000	USD
CY2013Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	49037000	USD
CY2013Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	55566000	USD
CY2013Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	2782000	USD
CY2013Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	1697000	USD
CY2013Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	1747000	USD
CY2013Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	1938000	USD
CY2013Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	2583000	USD
CY2013Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	5452000	USD
CY2012Q4	us-gaap	Other Assets Current OtherAssetsCurrent	28795000	USD
CY2013Q4	us-gaap	Other Assets Current OtherAssetsCurrent	25877000	USD
CY2012Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	19420000	USD
CY2013Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	27906000	USD
CY2012	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Costs Credit Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax	157000	USD
CY2013	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Costs Credit Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax	406000	USD
CY2011	us-gaap	Other Comprehensive Income Defined Benefit Plan Net Prior Service Costs Credit Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlanNetPriorServiceCostsCreditArisingDuringPeriodNetOfTax	325000	USD
CY2012	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-542000	USD
CY2011	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-7609000	USD
CY2013	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	8237000	USD
CY2012	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-296000	USD
CY2013	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	3813000	USD
CY2011	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-4135000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	-165000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	0	USD
CY2012	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Before Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditBeforeTax	0	USD
CY2012	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	-86000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	-176000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Amortization Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Prior Service Cost Credit Tax OtherComprehensiveIncomeLossAmortizationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetPriorServiceCostCreditTax	-185000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	18066000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-2610000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-9297000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	78918000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	40433000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	133028000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	0	USD
CY2011	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	0	USD
CY2013	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Before Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentBeforeTax	-1820000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Benefit Plan Improvement Tax Effect OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect	0	USD
CY2013	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Benefit Plan Improvement Tax Effect OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect	88000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Benefit Plan Improvement Tax Effect OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBenefitPlanImprovementTaxEffect	0	USD
CY2011	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
CY2012	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	0	USD
CY2013	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-971000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-4046000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	-1468000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesNetOfTax	643000	USD
CY2012	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	534000	USD
CY2013	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-2016000	USD
CY2011	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci On Derivatives Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIOnDerivativesTax	-709000	USD
CY2012	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-1268000	USD
CY2011	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	-2831000	USD
CY2013	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax	4534000	USD
CY2012	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-887000	USD
CY2011	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	-1708000	USD
CY2013	us-gaap	Other Comprehensive Income Unrealized Gain Loss On Derivatives Arising During Period Tax OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodTax	2445000	USD
CY2011	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	710000	USD
CY2012	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	2052000	USD
CY2013	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	1243000	USD
CY2012Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	125294000	USD
CY2013Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	133279000	USD
CY2011	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	5799000	USD
CY2012	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-4929000	USD
CY2013	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-9826000	USD
CY2013	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	694000	USD
CY2012	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	71000	USD
CY2011	us-gaap	Other Nonoperating Expense OtherNonoperatingExpense	817000	USD
CY2012	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	2486000	USD
CY2011	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	2490000	USD
CY2013	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	1971000	USD
CY2011	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	3726000	USD
CY2012	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	2965000	USD
CY2013	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	1798000	USD
CY2013	us-gaap	Payments For Derivative Instrument Financing Activities PaymentsForDerivativeInstrumentFinancingActivities	63939000	USD
CY2012	us-gaap	Payments For Derivative Instrument Financing Activities PaymentsForDerivativeInstrumentFinancingActivities	0	USD
CY2011	us-gaap	Payments For Derivative Instrument Financing Activities PaymentsForDerivativeInstrumentFinancingActivities	0	USD
CY2012	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	180000	USD
CY2013	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5471000	USD
CY2011	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4533000	USD
CY2013	us-gaap	Payments Of Dividends PaymentsOfDividends	67587000	USD
CY2012	us-gaap	Payments Of Dividends PaymentsOfDividends	65262000	USD
CY2011	us-gaap	Payments Of Dividends PaymentsOfDividends	59202000	USD
CY2013	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	354749000	USD
CY2011	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	440698000	USD
CY2012	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	349129000	USD
CY2011	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	14586000	USD
CY2012	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	20973000	USD
CY2013	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	22194000	USD
CY2013Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	111479000	USD
CY2012Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	167397000	USD
CY2011	us-gaap	Pension Contributions PensionContributions	11050000	USD
CY2013	us-gaap	Pension Contributions PensionContributions	12500000	USD
CY2012	us-gaap	Pension Contributions PensionContributions	25350000	USD
CY2013Q4	us-gaap	Preferred Stock Shares Authorized PreferredStockSharesAuthorized	25000000	shares
CY2013Q4	us-gaap	Preferred Stock Shares Outstanding PreferredStockSharesOutstanding	0	shares
CY2013	us-gaap	Previously Estimated Development Costs Incurred During Period PreviouslyEstimatedDevelopmentCostsIncurredDuringPeriod	-3554000	USD
CY2012	us-gaap	Previously Estimated Development Costs Incurred During Period PreviouslyEstimatedDevelopmentCostsIncurredDuringPeriod	-21931000	USD
CY2011	us-gaap	Previously Estimated Development Costs Incurred During Period PreviouslyEstimatedDevelopmentCostsIncurredDuringPeriod	-18940000	USD
CY2013	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2011	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	0	USD
CY2012	us-gaap	Proceeds From Divestiture Of Businesses ProceedsFromDivestitureOfBusinesses	107511000	USD
CY2013	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	4354000	USD
CY2012	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	4726000	USD
CY2011	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	123041000	USD
CY2011	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2013	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	800000000	USD
CY2012	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	USD
CY2011	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	1017300000	USD
CY2013	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	337650000	USD
CY2012	us-gaap	Proceeds From Lines Of Credit ProceedsFromLinesOfCredit	203753000	USD
CY2012	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2833000	USD
CY2013	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-15394000	USD
CY2011	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1666000	USD
CY2012	us-gaap	Proceeds From Sale Of Other Property Plant And Equipment ProceedsFromSaleOfOtherPropertyPlantAndEquipment	253791000	USD
CY2013	us-gaap	Proceeds From Sale Of Other Property Plant And Equipment ProceedsFromSaleOfOtherPropertyPlantAndEquipment	0	USD
CY2011	us-gaap	Proceeds From Sale Of Other Property Plant And Equipment ProceedsFromSaleOfOtherPropertyPlantAndEquipment	583000	USD
CY2013Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	4259445000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	3930772000	USD
CY2012	us-gaap	Property Plant And Equipment Gross Period Increase Decrease PropertyPlantAndEquipmentGrossPeriodIncreaseDecrease	347980000	USD
CY2013	us-gaap	Property Plant And Equipment Gross Period Increase Decrease PropertyPlantAndEquipmentGrossPeriodIncreaseDecrease	379534000	USD
CY2012Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2742749000	USD
CY2013Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	2990297000	USD
CY2013	us-gaap	Property Plant And Equipment Preproduction Design And Development Costs PropertyPlantAndEquipmentPreproductionDesignAndDevelopmentCosts	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Development Costs</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">According to accounting standards for business combinations, we expense, when incurred, development and acquisition costs associated with corporate development activities prior to acquiring or beginning construction of a project. Expensed development costs are included in Other operating expenses on the accompanying Consolidated Statements of Income.</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div></div>
CY2012	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	540000	USD
CY2013	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	607000	USD
CY2011	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	932000	USD
CY2012Q4	us-gaap	Regulatory Assets RegulatoryAssets	219393000	USD
CY2013Q4	us-gaap	Regulatory Assets RegulatoryAssets	162648000	USD
CY2012Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	31125000	USD
CY2013Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	24451000	USD
CY2013Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	138197000	USD
CY2012Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	188268000	USD
CY2012Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	141284000	USD
CY2013Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	120156000	USD
CY2013Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	10727000	USD
CY2012Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	13628000	USD
CY2013Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	109429000	USD
CY2012Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	127656000	USD
CY2011	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	8382000	USD
CY2013	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	445906000	USD
CY2013	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	532150000	USD
CY2011	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	821300000	USD
CY2012	us-gaap	Repayments Of Lines Of Credit RepaymentsOfLinesOfCredit	271753000	USD
CY2012	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	240077000	USD
CY2013Q4	us-gaap	Restricted Cash And Investments Current RestrictedCashAndInvestmentsCurrent	2000	USD
CY2012Q4	us-gaap	Restricted Cash And Investments Current RestrictedCashAndInvestmentsCurrent	7916000	USD
CY2011	us-gaap	Results Of Operations Depreciation Depletion And Amortization And Valuation Provisions ResultsOfOperationsDepreciationDepletionAndAmortizationAndValuationProvisions	34415000	USD
CY2013	us-gaap	Results Of Operations Depreciation Depletion And Amortization And Valuation Provisions ResultsOfOperationsDepreciationDepletionAndAmortizationAndValuationProvisions	20611000	USD
CY2012	us-gaap	Results Of Operations Depreciation Depletion And Amortization And Valuation Provisions ResultsOfOperationsDepreciationDepletionAndAmortizationAndValuationProvisions	37323000	USD
CY2013	us-gaap	Results Of Operations Expense From Oil And Gas Producing Activities ResultsOfOperationsExpenseFromOilAndGasProducingActivities	40751000	USD
CY2011	us-gaap	Results Of Operations Expense From Oil And Gas Producing Activities ResultsOfOperationsExpenseFromOilAndGasProducingActivities	58235000	USD
CY2012	us-gaap	Results Of Operations Expense From Oil And Gas Producing Activities ResultsOfOperationsExpenseFromOilAndGasProducingActivities	58545000	USD
CY2011	us-gaap	Results Of Operations Impairment Of Oil And Gas Properties ResultsOfOperationsImpairmentOfOilAndGasProperties	0	USD
CY2012	us-gaap	Results Of Operations Impairment Of Oil And Gas Properties ResultsOfOperationsImpairmentOfOilAndGasProperties	26868000	USD
CY2013	us-gaap	Results Of Operations Impairment Of Oil And Gas Properties ResultsOfOperationsImpairmentOfOilAndGasProperties	0	USD
CY2011	us-gaap	Results Of Operations Income Before Income Taxes ResultsOfOperationsIncomeBeforeIncomeTaxes	21573000	USD
CY2012	us-gaap	Results Of Operations Income Before Income Taxes ResultsOfOperationsIncomeBeforeIncomeTaxes	20527000	USD
CY2013	us-gaap	Results Of Operations Income Before Income Taxes ResultsOfOperationsIncomeBeforeIncomeTaxes	14133000	USD
CY2012	us-gaap	Results Of Operations Income Tax Expense ResultsOfOperationsIncomeTaxExpense	7082000	USD
CY2011	us-gaap	Results Of Operations Income Tax Expense ResultsOfOperationsIncomeTaxExpense	7442000	USD
CY2013	us-gaap	Results Of Operations Income Tax Expense ResultsOfOperationsIncomeTaxExpense	4876000	USD
CY2011	us-gaap	Results Of Operations Oil And Gas Producing Activities Net Income Excluding Corporate Overhead And Interest Costs ResultsOfOperationsOilAndGasProducingActivitiesNetIncomeExcludingCorporateOverheadAndInterestCosts	14131000	USD
CY2012	us-gaap	Results Of Operations Oil And Gas Producing Activities Net Income Excluding Corporate Overhead And Interest Costs ResultsOfOperationsOilAndGasProducingActivitiesNetIncomeExcludingCorporateOverheadAndInterestCosts	13445000	USD
CY2013	us-gaap	Results Of Operations Oil And Gas Producing Activities Net Income Excluding Corporate Overhead And Interest Costs ResultsOfOperationsOilAndGasProducingActivitiesNetIncomeExcludingCorporateOverheadAndInterestCosts	9257000	USD
CY2011	us-gaap	Results Of Operations Production Or Lifting Costs ResultsOfOperationsProductionOrLiftingCosts	23820000	USD
CY2013	us-gaap	Results Of Operations Production Or Lifting Costs ResultsOfOperationsProductionOrLiftingCosts	20140000	USD
CY2012	us-gaap	Results Of Operations Production Or Lifting Costs ResultsOfOperationsProductionOrLiftingCosts	23483000	USD
CY2011	us-gaap	Results Of Operations Revenue From Oil And Gas Producing Activities ResultsOfOperationsRevenueFromOilAndGasProducingActivities	79808000	USD
CY2013	us-gaap	Results Of Operations Revenue From Oil And Gas Producing Activities ResultsOfOperationsRevenueFromOilAndGasProducingActivities	54884000	USD
CY2012	us-gaap	Results Of Operations Revenue From Oil And Gas Producing Activities ResultsOfOperationsRevenueFromOilAndGasProducingActivities	79072000	USD
CY2012Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	492869000	USD
CY2013Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	540244000	USD
CY2011	us-gaap	Revisions Of Previous Quantity Estimates RevisionsOfPreviousQuantityEstimates	-58211000	USD
CY2012	us-gaap	Revisions Of Previous Quantity Estimates RevisionsOfPreviousQuantityEstimates	-86277000	USD
CY2013	us-gaap	Revisions Of Previous Quantity Estimates RevisionsOfPreviousQuantityEstimates	12851000	USD
CY2012	us-gaap	Sales And Transfers Of Oil And Gas Produced Net Of Production Costs SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts	48905000	USD
CY2013	us-gaap	Sales And Transfers Of Oil And Gas Produced Net Of Production Costs SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts	35932000	USD
CY2011	us-gaap	Sales And Transfers Of Oil And Gas Produced Net Of Production Costs SalesAndTransfersOfOilAndGasProducedNetOfProductionCosts	52914000	USD
CY2011	us-gaap	Sales Revenue Net SalesRevenueNet	1272188000	USD
CY2013	us-gaap	Sales Revenue Net SalesRevenueNet	1275852000	USD
CY2012	us-gaap	Sales Revenue Net SalesRevenueNet	1173884000	USD
CY2012Q4	us-gaap	Sales Revenue Net SalesRevenueNet	318862000	USD
CY2012Q3	us-gaap	Sales Revenue Net SalesRevenueNet	246808000	USD
CY2012Q1	us-gaap	Sales Revenue Net SalesRevenueNet	365851000	USD
CY2012Q2	us-gaap	Sales Revenue Net SalesRevenueNet	242363000	USD
CY2013Q3	us-gaap	Sales Revenue Net SalesRevenueNet	259907000	USD
CY2013Q4	us-gaap	Sales Revenue Net SalesRevenueNet	355448000	USD
CY2013Q1	us-gaap	Sales Revenue Net SalesRevenueNet	380671000	USD
CY2013Q2	us-gaap	Sales Revenue Net SalesRevenueNet	279826000	USD
CY2012Q4	us-gaap	Stockholders Equity StockholdersEquity	1232509000	USD
CY2013	us-gaap	Share Based Compensation ShareBasedCompensation	12595000	USD
CY2011	us-gaap	Share Based Compensation ShareBasedCompensation	5643000	USD
CY2012	us-gaap	Share Based Compensation ShareBasedCompensation	8271000	USD
CY2013Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	768953	shares
CY2013Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	82500000	USD
CY2012Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	277000000	USD
CY2013Q4	us-gaap	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	159425000	USD
CY2012Q4	us-gaap	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	136103000	USD
CY2011Q4	us-gaap	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	203357000	USD
CY2010Q4	us-gaap	Standardized Measure Of Discounted Future Net Cash Flows Relating To Proved Oil And Gas Reserves StandardizedMeasureOfDiscountedFutureNetCashFlowsRelatingToProvedOilAndGasReserves	168108000	USD
CY2012	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	3382000	USD
CY2013	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	3129000	USD
CY2011	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	3202000	USD
CY2011	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	119630000	USD
CY2011	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5076000	USD
CY2012	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	6040000	USD
CY2013	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	5867000	USD
CY2011Q4	us-gaap	Stockholders Equity StockholdersEquity	1209336000	USD
CY2010Q4	us-gaap	Stockholders Equity StockholdersEquity	1100270000	USD
CY2013Q4	us-gaap	Stockholders Equity StockholdersEquity	1307748000	USD
CY2013Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1307748000	USD
CY2012Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1232509000	USD
CY2013	us-gaap	Stockholders Equity Other StockholdersEquityOther	-392000	USD
CY2011	us-gaap	Stockholders Equity Other StockholdersEquityOther	45000	USD
CY2012	us-gaap	Stockholders Equity Other StockholdersEquityOther	22000	USD
CY2011	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	33710000	USD
CY2012	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	40487000	USD
CY2013	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	40012000	USD
CY2012Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	71782	shares
CY2013Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	50877	shares
CY2013Q4	us-gaap	Treasury Stock Value TreasuryStockValue	1968000	USD
CY2012Q4	us-gaap	Treasury Stock Value TreasuryStockValue	2245000	USD
CY2012	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	1882000	USD
CY2013	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	30169000	USD
CY2011	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-42010000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	4578000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	8906000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	3533000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2013	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2013	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1526000	USD
CY2013Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	1700000	USD
CY2013Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fifth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFifthAnniversary	110930000	USD
CY2013Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On First Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary	203131000	USD
CY2013Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Fourth Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnFourthAnniversary	125492000	USD
CY2011	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	1400000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	151000	USD
CY2013Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	9900000	USD
CY2012Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	8300000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	1600000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	1400000	USD
CY2013	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	0	USD
CY2011	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	2725000	USD
CY2012	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	111000	USD
CY2013Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Second Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnSecondAnniversary	148874000	USD
CY2013Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Balance On Third Anniversary UnrecordedUnconditionalPurchaseObligationBalanceOnThirdAnniversary	136503000	USD
CY2013Q4	us-gaap	Unrecorded Unconditional Purchase Obligation Due After Five Years UnrecordedUnconditionalPurchaseObligationDueAfterFiveYears	148362000	USD
CY2013	us-gaap	Use Of Estimates UseOfEstimates	<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Use of Estimates and Basis of Presentation</font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br clear="none"/></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">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.</font></div></div>
CY2013	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	261919000	USD
CY2011	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	247496000	USD
CY2012	us-gaap	Utilities Operating Expense Maintenance Operations And Other Costs And Expenses UtilitiesOperatingExpenseMaintenanceOperationsAndOtherCostsAndExpenses	242367000	USD
CY2011	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	0	USD
CY2013	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	0	USD
CY2012	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	0	USD
CY2012Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	768000	USD
CY2011Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	1661000	USD
CY2010Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	2295000	USD
CY2013Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	1237000	USD
CY2013	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	2780000	USD
CY2011	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	3042000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	1913000	USD
CY2011	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	9045000	USD
CY2013	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	7310000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	6628000	USD
CY2013	bkh	Effective Income Tax Rate Reconciliation Allowance For Other Funds Used During Construction Equity EffectiveIncomeTaxRateReconciliationAllowanceForOtherFundsUsedDuringConstructionEquity	0.000
CY2011	us-gaap	Valuation Allowances And Reserves Recoveries ValuationAllowancesAndReservesRecoveries	5369000	USD
CY2012	us-gaap	Valuation Allowances And Reserves Recoveries ValuationAllowancesAndReservesRecoveries	3822000	USD
CY2011	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	40081000	shares
CY2011	bkh	Average Crude Oil Price Per Barrel Nymex AverageCrudeOilPricePerBarrelNYMEX	96.19
CY2013	bkh	Average Crude Oil Price Per Barrel Nymex AverageCrudeOilPricePerBarrelNYMEX	96.94
CY2013	bkh	Average Crude Oil Price Per Barrel Wellhead AverageCrudeOilPricePerBarrelWellhead	89.79
CY2012	bkh	Average Crude Oil Price Per Barrel Wellhead AverageCrudeOilPricePerBarrelWellhead	85.31
CY2013	us-gaap	Valuation Allowances And Reserves Recoveries ValuationAllowancesAndReservesRecoveries	4999000	USD
CY2013	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	44419000	shares
CY2012	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	44073000	shares
CY2013	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	44163000	shares
CY2011	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	39864000	shares
CY2012	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	43820000	shares
CY2013Q4	us-gaap	Wells In Process Of Drilling WellsInProcessOfDrilling	1224
CY2012	bkh	Average Crude Oil Price Per Barrel Nymex AverageCrudeOilPricePerBarrelNYMEX	94.71
CY2011	bkh	Average Crude Oil Price Per Barrel Wellhead AverageCrudeOilPricePerBarrelWellhead	88.49
CY2012	bkh	Average Natural Gas Price Per Mcfnymex AverageNaturalGasPricePerMCFNYMEX	2.76
CY2013	bkh	Average Natural Gas Price Per Mcfnymex AverageNaturalGasPricePerMCFNYMEX	3.67
CY2011	bkh	Average Natural Gas Price Per Mcfnymex AverageNaturalGasPricePerMCFNYMEX	4.12
CY2012	bkh	Average Natural Gas Price Per Mcf Wellhead AverageNaturalGasPricePerMCFWellhead	2.24
CY2013	bkh	Average Natural Gas Price Per Mcf Wellhead AverageNaturalGasPricePerMCFWellhead	3.45
CY2011	bkh	Average Natural Gas Price Per Mcf Wellhead AverageNaturalGasPricePerMCFWellhead	3.59
CY2011	bkh	Capitalized Interest CapitalizedInterest	11260000	USD
CY2013	bkh	Capitalized Interest CapitalizedInterest	1061000	USD
CY2012	bkh	Capitalized Interest CapitalizedInterest	682000	USD
CY2013	bkh	Capitalized Interest Of Cost Excluded From Amortization CapitalizedInterestOfCostExcludedFromAmortization	4922000	USD
CY2013Q4	bkh	Credit Exposure Non Investment Grade Company CreditExposureNonInvestmentGradeCompany	500000	USD
CY2013Q4	bkh	Deferred Tax Liabilities Development Operations DeferredTaxLiabilitiesDevelopmentOperations	69799000	USD
CY2012Q4	bkh	Deferred Tax Liabilities Development Operations DeferredTaxLiabilitiesDevelopmentOperations	48411000	USD
CY2012Q4	bkh	Deferred Tax Liability State DeferredTaxLiabilityState	19986000	USD
CY2013Q4	bkh	Deferred Tax Liability State DeferredTaxLiabilityState	30293000	USD
CY2013	bkh	Defined Contribution Plan Employee Vesting Period DefinedContributionPlanEmployeeVestingPeriod	P5Y
CY2011	bkh	Effective Income Tax Rate Reconciliation Allowance For Other Funds Used During Construction Equity EffectiveIncomeTaxRateReconciliationAllowanceForOtherFundsUsedDuringConstructionEquity	-0.005
CY2012	bkh	Effective Income Tax Rate Reconciliation Allowance For Other Funds Used During Construction Equity EffectiveIncomeTaxRateReconciliationAllowanceForOtherFundsUsedDuringConstructionEquity	0.000
CY2013	bkh	Effective Income Tax Rate Reconciliation Flow Through Accounting EffectiveIncomeTaxRateReconciliationFlowThroughAccounting	-0.009
CY2012	bkh	Effective Income Tax Rate Reconciliation Flow Through Accounting EffectiveIncomeTaxRateReconciliationFlowThroughAccounting	-0.013
CY2011	bkh	Effective Income Tax Rate Reconciliation Flow Through Accounting EffectiveIncomeTaxRateReconciliationFlowThroughAccounting	-0.045
CY2013	bkh	Effective Tax Rate Reconciliation Investment Tax Credits And Excess Deferred EffectiveTaxRateReconciliationInvestmentTaxCreditsAndExcessDeferred	-0.001
CY2013Q4	bkh	Depreciation Depletion And Amortization Remaining Amortization Period DepreciationDepletionAndAmortizationRemainingAmortizationPeriod	P17Y
CY2012	bkh	Effective Tax Rate Reconciliation Investment Tax Credits And Excess Deferred EffectiveTaxRateReconciliationInvestmentTaxCreditsAndExcessDeferred	-0.002
CY2011	bkh	Effective Tax Rate Reconciliation Investment Tax Credits And Excess Deferred EffectiveTaxRateReconciliationInvestmentTaxCreditsAndExcessDeferred	-0.005
CY2013	bkh	Estimated Future Development Costsof Proved Undeveloped Wells EstimatedFutureDevelopmentCostsofProvedUndevelopedWells	15900000	USD
CY2012	bkh	Finite Lived Intangible Asset Purchase Accounting Adjustments FiniteLivedIntangibleAssetPurchaseAccountingAdjustments	0	USD
CY2011	bkh	Finite Lived Intangible Asset Purchase Accounting Adjustments FiniteLivedIntangibleAssetPurchaseAccountingAdjustments	0	USD
CY2013	bkh	Finite Lived Intangible Asset Purchase Accounting Adjustments FiniteLivedIntangibleAssetPurchaseAccountingAdjustments	0	USD
CY2011	bkh	Fuel Purchased Power And Cost Of Gas Sold FuelPurchasedPowerAndCostOfGasSold	574989000	USD
CY2012	bkh	Fuel Purchased Power And Cost Of Gas Sold FuelPurchasedPowerAndCostOfGasSold	407066000	USD
CY2013	bkh	Fuel Purchased Power And Cost Of Gas Sold FuelPurchasedPowerAndCostOfGasSold	492147000	USD
CY2012Q4	bkh	Gain Loss On Sale Of Oil And Gas Properties After Tax GainLossOnSaleOfOilAndGasPropertiesAfterTax	1200000	USD
CY2012Q3	bkh	Gain Loss On Sale Of Oil And Gas Properties After Tax GainLossOnSaleOfOilAndGasPropertiesAfterTax	18000000	USD
CY2012Q4	bkh	Gross Amounts Offset In Statement Of Financial Position Assets GrossAmountsOffsetInStatementOfFinancialPositionAssets	1586000	USD
CY2013Q4	bkh	Gross Amounts Offset In Statement Of Financial Position Assets GrossAmountsOffsetInStatementOfFinancialPositionAssets	3258000	USD
CY2012Q4	bkh	Gross Amounts Offset In Statement Of Financial Position Liabilities GrossAmountsOffsetInStatementOfFinancialPositionLiabilities	15942000	USD
CY2013Q4	bkh	Gross Amounts Offset In Statement Of Financial Position Liabilities GrossAmountsOffsetInStatementOfFinancialPositionLiabilities	10860000	USD
CY2012Q2	bkh	Impairment Of Oil And Gas Properties Net Of Tax ImpairmentOfOilAndGasPropertiesNetOfTax	17000000	USD
CY2013	bkh	Incremental Common Shares Attributable To Other Dilutive Securities IncrementalCommonSharesAttributableToOtherDilutiveSecurities	0	shares
CY2011	bkh	Incremental Common Shares Attributable To Other Dilutive Securities IncrementalCommonSharesAttributableToOtherDilutiveSecurities	3000	shares
CY2012	bkh	Incremental Common Shares Attributable To Other Dilutive Securities IncrementalCommonSharesAttributableToOtherDilutiveSecurities	3000	shares
CY2012Q4	bkh	Net Derivative Position Assets NetDerivativePositionAssets	3746000	USD
CY2013Q4	bkh	Net Derivative Position Assets NetDerivativePositionAssets	717000	USD
CY2013Q4	bkh	Net Derivative Position Liabilities NetDerivativePositionLiabilities	4067000	USD
CY2012Q4	bkh	Net Derivative Position Liabilities NetDerivativePositionLiabilities	107341000	USD
CY2011	bkh	Non Cash Revision To Capitalized Asset Retirement Costs NonCashRevisionToCapitalizedAssetRetirementCosts	-1525000	USD
CY2012	bkh	Non Cash Revision To Capitalized Asset Retirement Costs NonCashRevisionToCapitalizedAssetRetirementCosts	5743000	USD
CY2013	bkh	Non Cash Revision To Capitalized Asset Retirement Costs NonCashRevisionToCapitalizedAssetRetirementCosts	1235000	USD
CY2013	bkh	Number Of Business Groups NumberOfBusinessGroups	2	Business_Group
CY2012	bkh	Operating Costs Nonregulated Energy Operations OperatingCostsNonregulatedEnergyOperations	85830000	USD
CY2013	bkh	Operating Costs Nonregulated Energy Operations OperatingCostsNonregulatedEnergyOperations	83762000	USD
CY2011	bkh	Operating Costs Nonregulated Energy Operations OperatingCostsNonregulatedEnergyOperations	93453000	USD
CY2013Q4	bkh	Proved Undeveloped Reserve Locations ProvedUndevelopedReserveLocations	23	PUD_Location
CY2013	bkh	Proved Undeveloped Reserves ProvedUndevelopedReserves	4400000	Mcfe
CY2013	bkh	Proved Undeveloped Reserves Extensions Discoveries And Additions ProvedUndevelopedReservesExtensionsDiscoveriesAndAdditions	12700000	Mcfe
CY2013	bkh	Proved Undeveloped Reserves Revisions Of Previous Estimates ProvedUndevelopedReservesRevisionsOfPreviousEstimates	0	Mcfe
CY2013	bkh	Public Utilities Allowance For Funds Used During Construction Borrowed Interest Costs Capitalized PublicUtilitiesAllowanceForFundsUsedDuringConstructionBorrowedInterestCostsCapitalized	1130000	USD
CY2011	bkh	Public Utilities Allowance For Funds Used During Construction Borrowed Interest Costs Capitalized PublicUtilitiesAllowanceForFundsUsedDuringConstructionBorrowedInterestCostsCapitalized	14041000	USD
CY2012	bkh	Public Utilities Allowance For Funds Used During Construction Borrowed Interest Costs Capitalized PublicUtilitiesAllowanceForFundsUsedDuringConstructionBorrowedInterestCostsCapitalized	3462000	USD
CY2013Q4	bkh	Pud Locations In Reserves For Five Or More Years PudLocationsInReservesForFiveOrMoreYears	0	PUD_Location
CY2013	bkh	Reserves Replaced ReservesReplaced	0.90
CY2013	bkh	Results Of Operations Gain Loss On Sale ResultsOfOperationsGainLossOnSale	0	USD
CY2011	bkh	Results Of Operations Gain Loss On Sale ResultsOfOperationsGainLossOnSale	0	USD
CY2012	bkh	Results Of Operations Gain Loss On Sale ResultsOfOperationsGainLossOnSale	29129000	USD
CY2013	bkh	Total Other Income Expense TotalOtherIncomeExpense	-78012000	USD
CY2011	bkh	Total Other Income Expense TotalOtherIncomeExpense	-128771000	USD
CY2012	bkh	Total Other Income Expense TotalOtherIncomeExpense	-106816000	USD
CY2012Q2	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	-10000000	USD
CY2012Q1	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	7800000	USD
CY2013Q3	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	2000000	USD
CY2013Q2	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	12000000	USD
CY2013Q4	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	500000	USD
CY2012Q4	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	3100000	USD
CY2012Q3	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	400000	USD
CY2013Q1	bkh	Unrealized Gain Losson Unhedged Derivative Instrument Net Of Tax UnrealizedGainLossonUnhedgedDerivativeInstrumentNetOfTax	4800000	USD
CY2013	dei	Amendment Flag AmendmentFlag	false
CY2013	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2013	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2013	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2013
CY2013	dei	Document Period End Date DocumentPeriodEndDate	2013-12-31
CY2013	dei	Document Type DocumentType	10-K
CY2013	dei	Entity Central Index Key EntityCentralIndexKey	0001130464
CY2014Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	44503454	shares
CY2013	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2013	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2013Q2	dei	Entity Public Float EntityPublicFloat	2135998459	USD
CY2013	dei	Entity Registrant Name EntityRegistrantName	BLACK HILLS CORP /SD/
CY2013	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2013	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes

Files In Submission

Name	View Source	Status
0001130464-14-000056-index-headers.html	Edgar Link	pending
0001130464-14-000056-index.html	Edgar Link	pending
0001130464-14-000056.txt	Edgar Link	pending
0001130464-14-000056-xbrl.zip	Edgar Link	pending
bkh-20131231.xml	Edgar Link	completed
bkh-20131231.xsd	Edgar Link	pending
bkh-20131231_cal.xml	Edgar Link	unprocessable
bkh-20131231_def.xml	Edgar Link	unprocessable
bkh-20131231_lab.xml	Edgar Link	unprocessable
bkh-20131231_pre.xml	Edgar Link	unprocessable
bkh10k12312013.htm	Edgar Link	pending
bkhex-1010122013.htm	Edgar Link	pending
bkhex-1012122013.htm	Edgar Link	pending
bkhex-107122013.htm	Edgar Link	pending
bkhex-109122013.htm	Edgar Link	pending
bkhex-21122013.htm	Edgar Link	pending
bkhex-231122013.htm	Edgar Link	pending
bkhex-232122013.htm	Edgar Link	pending
bkhex-311122013.htm	Edgar Link	pending
bkhex-312122013.htm	Edgar Link	pending
bkhex-321122013.htm	Edgar Link	pending
bkhex-322122013.htm	Edgar Link	pending
exhibit95minesafetydata122.htm	Edgar Link	pending
exhibit99oilandgas122013.htm	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xls	Edgar Link	pending
Financial_Report.xlsx	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R100.htm	Edgar Link	pending
R101.htm	Edgar Link	pending
R102.htm	Edgar Link	pending
R103.htm	Edgar Link	pending
R104.htm	Edgar Link	pending
R105.htm	Edgar Link	pending
R106.htm	Edgar Link	pending
R107.htm	Edgar Link	pending
R108.htm	Edgar Link	pending
R109.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R110.htm	Edgar Link	pending
R111.htm	Edgar Link	pending
R112.htm	Edgar Link	pending
R113.htm	Edgar Link	pending
R114.htm	Edgar Link	pending
R115.htm	Edgar Link	pending
R116.htm	Edgar Link	pending
R117.htm	Edgar Link	pending
R118.htm	Edgar Link	pending
R119.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R120.htm	Edgar Link	pending
R121.htm	Edgar Link	pending
R122.htm	Edgar Link	pending
R123.htm	Edgar Link	pending
R124.htm	Edgar Link	pending
R125.htm	Edgar Link	pending
R126.htm	Edgar Link	pending
R127.htm	Edgar Link	pending
R128.htm	Edgar Link	pending
R129.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
R130.htm	Edgar Link	pending
R131.htm	Edgar Link	pending
R132.htm	Edgar Link	pending
R133.htm	Edgar Link	pending
R134.htm	Edgar Link	pending
R135.htm	Edgar Link	pending
R136.htm	Edgar Link	pending
R137.htm	Edgar Link	pending
R138.htm	Edgar Link	pending
R139.htm	Edgar Link	pending
R14.htm	Edgar Link	pending
R140.htm	Edgar Link	pending
R141.htm	Edgar Link	pending
R15.htm	Edgar Link	pending
R16.htm	Edgar Link	pending
R17.htm	Edgar Link	pending
R18.htm	Edgar Link	pending
R19.htm	Edgar Link	pending
R2.htm	Edgar Link	pending
R20.htm	Edgar Link	pending
R21.htm	Edgar Link	pending
R22.htm	Edgar Link	pending
R23.htm	Edgar Link	pending
R24.htm	Edgar Link	pending
R25.htm	Edgar Link	pending
R26.htm	Edgar Link	pending
R27.htm	Edgar Link	pending
R28.htm	Edgar Link	pending
R29.htm	Edgar Link	pending
R3.htm	Edgar Link	pending
R30.htm	Edgar Link	pending
R31.htm	Edgar Link	pending
R32.htm	Edgar Link	pending
R33.htm	Edgar Link	pending
R34.htm	Edgar Link	pending
R35.htm	Edgar Link	pending
R36.htm	Edgar Link	pending
R37.htm	Edgar Link	pending
R38.htm	Edgar Link	pending
R39.htm	Edgar Link	pending
R4.htm	Edgar Link	pending
R40.htm	Edgar Link	pending
R41.htm	Edgar Link	pending
R42.htm	Edgar Link	pending
R43.htm	Edgar Link	pending
R44.htm	Edgar Link	pending
R45.htm	Edgar Link	pending
R46.htm	Edgar Link	pending
R47.htm	Edgar Link	pending
R48.htm	Edgar Link	pending
R49.htm	Edgar Link	pending
R5.htm	Edgar Link	pending
R50.htm	Edgar Link	pending
R51.htm	Edgar Link	pending
R52.htm	Edgar Link	pending
R53.htm	Edgar Link	pending
R54.htm	Edgar Link	pending
R55.htm	Edgar Link	pending
R56.htm	Edgar Link	pending
R57.htm	Edgar Link	pending
R58.htm	Edgar Link	pending
R59.htm	Edgar Link	pending
R6.htm	Edgar Link	pending
R60.htm	Edgar Link	pending
R61.htm	Edgar Link	pending
R62.htm	Edgar Link	pending
R63.htm	Edgar Link	pending
R64.htm	Edgar Link	pending
R65.htm	Edgar Link	pending
R66.htm	Edgar Link	pending
R67.htm	Edgar Link	pending
R68.htm	Edgar Link	pending
R69.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R70.htm	Edgar Link	pending
R71.htm	Edgar Link	pending
R72.htm	Edgar Link	pending
R73.htm	Edgar Link	pending
R74.htm	Edgar Link	pending
R75.htm	Edgar Link	pending
R76.htm	Edgar Link	pending
R77.htm	Edgar Link	pending
R78.htm	Edgar Link	pending
R79.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R80.htm	Edgar Link	pending
R81.htm	Edgar Link	pending
R82.htm	Edgar Link	pending
R83.htm	Edgar Link	pending
R84.htm	Edgar Link	pending
R85.htm	Edgar Link	pending
R86.htm	Edgar Link	pending
R87.htm	Edgar Link	pending
R88.htm	Edgar Link	pending
R89.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
R90.htm	Edgar Link	pending
R91.htm	Edgar Link	pending
R92.htm	Edgar Link	pending
R93.htm	Edgar Link	pending
R94.htm	Edgar Link	pending
R95.htm	Edgar Link	pending
R96.htm	Edgar Link	pending
R97.htm	Edgar Link	pending
R98.htm	Edgar Link	pending
R99.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending
usmapbw.jpg	Edgar Link	pending

Create your account

Find Stocks Worth Researching

Deeply Understand Businesses

Value Businesses Intelligently

$BKH
BLACK HILLS CORP /SD/ Stock $bkh

2013 Form 10-K Financial Statement

#000113046414000056 Filed on February 26, 2014

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKH BLACK HILLS CORP /SD/ Stock $bkh

2013 Form 10-K Financial Statement

#000113046414000056 Filed on February 26, 2014

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$BKH
BLACK HILLS CORP /SD/ Stock $bkh