2.2.0.7 false Condensed Statements of Consolidated Income (Loss) (unaudited) (USD $) 0110 - Statement - Condensed Statements of Consolidated Income (Loss) (unaudited) true false In Millions, except Per Share data false false 1 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 3 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 4 USD false false USD Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 USDEPS Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 Shares Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 3 Net Revenues 1 us-gaap_GrossProfitAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 4 Gas Distribution 2 us-gaap_GasDomesticRegulatedRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 true true false false 454300000 454.3 false false false 2 true true false false 444700000 444.7 false false false 3 true true false false 1795400000 1795.4 false false false 4 true true false false 2161600000 2161.6 false false false xbrli:monetaryItemType monetary Revenue derived from the regulated (by a federal, state, or local government or agency) generation, transmission and distribution of [natural] gas. No authoritative reference available. false 5 Gas Transportation and Storage 2 us-gaap_NaturalGasMidstreamRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 264300000 264.3 false false false 2 false true false false 260200000 260.2 false false false 3 false true false false 634800000 634.8 false false false 4 false true false false 656300000 656.3 false false false xbrli:monetaryItemType monetary Midstream refers to those gas industry activities that fall between exploration and production (upstream) and refining and marketing (downstream). It may be applied to the gathering, processing, transmission and storage of natural gas; including the treating of natural gas to remove impurities, along with the sale of by-products such as residue gas, natural gas liquids and condensate. No authoritative reference available. false 6 Electric 2 us-gaap_ElectricDomesticRegulatedRevenue us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 340500000 340.5 false false false 2 false true false false 285400000 285.4 false false false 3 false true false false 658400000 658.4 false false false 4 false true false false 582200000 582.2 false false false xbrli:monetaryItemType monetary Revenue derived from the regulated (by a federal, state, or local government or agency) generation, transmission and distribution of electricity. No authoritative reference available. false 7 Other 2 us-gaap_OtherSalesRevenueNet us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 112000000 112.0 false false false 2 false true false false 278300000 278.3 false false false 3 false true false false 441200000 441.2 false false false 4 false true false false 590400000 590.4 false false false xbrli:monetaryItemType monetary Revenues from the sale of other goods or rendering of other services, not elsewhere specified in the taxonomy; net of (reduced by) sales adjustments, returns, allowances, and discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 true 8 Gross Revenues 2 us-gaap_SalesRevenueNet us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 1171100000 1171.1 false false false 2 false true false false 1268600000 1268.6 false false false 3 false true false false 3529800000 3529.8 false false false 4 false true false false 3990500000 3990.5 false false false xbrli:monetaryItemType monetary Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 false 9 Cost of Sales (excluding depreciation and amortization) 2 ni_CostOfSalesExcludingDepreciationAndAmortization ni false debit duration Cost of Sales (excluding depreciation and amortization). false false false false false false false false false false false totallabel false 1 false true false false 439100000 439.1 false false false 2 false true false false 586800000 586.8 false false false 3 false true false false 1725400000 1725.4 false false false 4 false true false false 2242300000 2242.3 false false false xbrli:monetaryItemType monetary Cost of Sales (excluding depreciation and amortization). No authoritative reference available. true 10 Total Net Revenues 2 us-gaap_GrossProfit us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 732000000 732.0 false false false 2 false true false false 681800000 681.8 false false false 3 false true false false 1804400000 1804.4 false false false 4 false true false false 1748200000 1748.2 false false false xbrli:monetaryItemType monetary Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity. No authoritative reference available. true 11 Operating Expenses 1 us-gaap_OperatingExpensesAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 12 Operation and maintenance 2 us-gaap_UtilitiesOperatingExpenseMaintenanceAndOperations us-gaap true debit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 377100000 377.1 false false false 2 false true false false 365200000 365.2 false false false 3 false true false false 816700000 816.7 false false false 4 false true false false 844700000 844.7 false false false xbrli:monetaryItemType monetary Discloses the amount of operating expense for the period for routine plant maintenance, repairs and operations. No authoritative reference available. false 13 Depreciation and amortization 2 us-gaap_DepreciationDepletionAndAmortization us-gaap true debit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 151600000 151.6 false false false 2 false true false false 148200000 148.2 false false false 3 false true false false 301400000 301.4 false false false 4 false true false false 291900000 291.9 false false false xbrli:monetaryItemType monetary The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets. No authoritative reference available. false 14 Impairment and loss/(gain) on sale of assets, net 2 ni_ImpairmentAndGainLossOnSaleOfAssetsNet ni false debit duration Impairment and (gain)/loss on sale of assets, net. false false false false false false false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false true false false 800000 0.8 false false false 3 false true false false 100000 0.1 false false false 4 false true false false -1200000 -1.2 false false false xbrli:monetaryItemType monetary Impairment and (gain)/loss on sale of assets, net. No authoritative reference available. false 15 Other taxes 2 us-gaap_TaxesExcludingIncomeAndExciseTaxes us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 64500000 64.5 false false false 2 false true false false 53300000 53.3 false false false 3 false true false false 151400000 151.4 false false false 4 false true false false 156700000 156.7 false false false xbrli:monetaryItemType monetary All taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax. No authoritative reference available. true 16 Total Operating Expenses 2 us-gaap_OperatingExpenses us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 593200000 593.2 false false false 2 false true false false 567500000 567.5 false false false 3 false true false false 1269600000 1269.6 false false false 4 false true false false 1292100000 1292.1 false false false xbrli:monetaryItemType monetary Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. No authoritative reference available. true 17 Equity Earnings (Loss) in Unconsolidated Affiliates 1 us-gaap_IncomeLossFromEquityMethodInvestments us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 400000 0.4 false false false 2 false true false false -2600000 -2.6 false false false 3 false true false false 7800000 7.8 false false false 4 false true false false 3800000 3.8 false false false xbrli:monetaryItemType monetary This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. Such amount typically reflects adjustments similar to those made in preparing consolidated statements, including adjustments to eliminate intercompany gains and losses, and to amortize, if appropriate, any difference between cost and underlying equity in net assets of the investee at the date of investment. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -Subparagraph c Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 6 -Subparagraph b true 18 Operating Income 1 us-gaap_OperatingIncomeLoss us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 139200000 139.2 false false false 2 false true false false 111700000 111.7 false false false 3 false true false false 542600000 542.6 false false false 4 false true false false 459900000 459.9 false false false xbrli:monetaryItemType monetary The net result for the period of deducting operating expenses from operating revenues. No authoritative reference available. true 19 Other Income (Deductions) 1 us-gaap_OtherNonoperatingIncomeExpenseAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 20 Interest expense, net 2 us-gaap_InterestExpense us-gaap true debit duration No definition available. false false false false false false false false false false true negated false 1 false true false false -98400000 -98.4 false false false 2 false true false false -105300000 -105.3 false false false 3 false true false false -197200000 -197.2 false false false 4 false true false false -195800000 -195.8 false false false xbrli:monetaryItemType monetary The cost of borrowed funds accounted for as interest that was charged against earnings during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 34 -Paragraph 21 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Chapter V -Section 563c.102 -Paragraph 9 -Subsection II Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 9 -Article 9 false 21 Other, net 2 us-gaap_OtherNonoperatingIncomeExpense us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 2600000 2.6 false false false 2 false true false false -500000 -0.5 false false false 3 false true false false 5200000 5.2 false false false 4 false true false false -4700000 -4.7 false false false xbrli:monetaryItemType monetary The net amount of other nonoperating income and expense, which does not qualify for separate disclosure on the income statement under materiality guidelines. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 9 -Article 5 false 22 Gain/(Loss) on early extinguishment of long-term debt 2 us-gaap_GainsLossesOnExtinguishmentOfDebt us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false false false false 0 0 false false false 2 false true false false -700000 -0.7 false false false 3 false false false false 0 0 false false false 4 false true false false 2500000 2.5 false false false xbrli:monetaryItemType monetary Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 26 -Paragraph 20, 21 true 23 Total Other Deductions 2 us-gaap_NonoperatingIncomeExpense us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false -95800000 -95.8 false false false 2 false true false false -106500000 -106.5 false false false 3 false true false false -192000000 -192.0 false false false 4 false true false false -198000000 -198.0 false false false xbrli:monetaryItemType monetary The aggregate amount of income (expense) from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 7 -Article 5 true 24 Income from Continuing Operations before Income Taxes 1 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic us-gaap true credit duration No definition available. false false false false false false false false false false false verboselabel false 1 false true false false 43400000 43.4 false false false 2 false true false false 5200000 5.2 false false false 3 false true false false 350600000 350.6 false false false 4 false true false false 261900000 261.9 false false false xbrli:monetaryItemType monetary The portion of earnings (loss) from continuing operations before income taxes that is attributable to domestic operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Subparagraph 1(i) -Article 4 false 25 Income Taxes 1 us-gaap_IncomeTaxExpenseBenefit us-gaap true debit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 15400000 15.4 false false false 2 false true false false 9200000 9.2 false false false 3 false true false false 125200000 125.2 false false false 4 false true false false 106700000 106.7 false false false xbrli:monetaryItemType monetary The sum of the current income tax expense (benefit) and the deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 08 -Paragraph h -Article 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 109 -Paragraph 45 -Subparagraph a, b true 26 Income (Loss) from Continuing Operations 1 us-gaap_IncomeLossFromContinuingOperations us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 28000000 28.0 false false false 2 false true false false -4000000 -4.0 false false false 3 false true false false 225400000 225.4 false false false 4 false true false false 155200000 155.2 false false false xbrli:monetaryItemType monetary This element represents the income or loss from continuing operations attributable to the reporting entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items and cumulative effects of changes in accounting principles, but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 28 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph b(1) true 27 Income/(Loss) from Discontinued Operations - net of taxes 1 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity us-gaap true credit duration No definition available. false false false false false false false false false false false terselabel false 1 false true false false 100000 0.1 false false false 2 false true false false -700000 -0.7 false false false 3 false true false false -100000 -0.1 false false false 4 false true false false -11400000 -11.4 false false false xbrli:monetaryItemType monetary This element represents the overall income (loss) from a disposal group apportioned to the parent that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items and the cumulative effect of accounting changes after deduction or consideration of the amount which may be allocable to noncontrolling interests, if any. Includes the following (net of tax): income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 28 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph b(2) false 28 Gain (Loss) on Disposition of Discontinued Operations - net of taxes 1 us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false false false false 0 0 false false false 2 false true false false -100000 -0.1 false false false 3 false true false false 100000 0.1 false false false 4 false true false false -200000 -0.2 false false false xbrli:monetaryItemType monetary Gain (loss) after tax expense (benefit), not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 43 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -Subparagraph b true 29 Net Income (Loss) 1 us-gaap_NetIncomeLoss us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 true true false false 28100000 28.1 false false false 2 true true false false -4800000 -4.8 false false false 3 true true false false 225400000 225.4 false false false 4 true true false false 143600000 143.6 false false false xbrli:monetaryItemType monetary The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph d Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A7 -Appendix A Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 10, 15 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28, 29, 30 true 30 Basic Earnings (Loss) Per Share 1 us-gaap_EarningsPerShareBasicAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 31 Continuing operations 2 us-gaap_IncomeLossFromContinuingOperationsPerBasicShare us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel true 1 true true false false 0.1 0.1 false false false 2 true true false false -0.01 -0.01 false false false 3 true true false false 0.81 0.81 false false false 4 true true false false 0.57 0.57 false false false us-types:perShareItemType decimal The amount of income (loss) from continuing operations per each share of common stock outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 36, 37, 38 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 false 32 Discontinued operations 2 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare us-gaap true na duration No definition available. false false false false false false false false false false false totallabel true 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 true true false false -0.04 -0.04 false false false us-types:perShareItemType decimal The amount of income (loss) from disposition of discontinued operations, net of related tax effect, per each share of common stock outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 8, 9, 10, 36, 37, 38 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 true 33 Basic Earnings (Loss) Per Share 2 us-gaap_EarningsPerShareBasic us-gaap true na duration No definition available. false false false false false false false false false false false totallabel true 1 true true false false 0.1 0.1 false false false 2 true true false false -0.01 -0.01 false false false 3 true true false false 0.81 0.81 false false false 4 true true false false 0.53 0.53 false false false us-types:perShareItemType decimal The amount of net income or loss for the period per each share of common stock outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 36, 37, 38 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 true 34 Diluted Earnings (Loss) Per Share 1 us-gaap_EarningsPerShareDilutedAbstract us-gaap true na duration No definition available. false false false false false true false false false false false verboselabel false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 35 Continuing operations 2 us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare us-gaap true na duration No definition available. false false false false false false false false false false false verboselabel true 1 true true false false 0.1 0.1 false false false 2 true true false false -0.01 -0.01 false false false 3 true true false false 0.81 0.81 false false false 4 true true false false 0.56 0.56 false false false us-types:perShareItemType decimal The amount of income (loss) from continuing operations available to each share of common stock outstanding during the reporting period and each share that would have been outstanding assuming the issuance of common shares for all dilutive potential common shares outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 21 -Article 9 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 11, 12, 36, 37, 38 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 128 -Paragraph 40 -Subparagraph a Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 20 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 18 -Article 7 false 36 Discontinued operations 2 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare us-gaap true na duration No definition available. false false false false false false false false false false false totallabel true 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 true true false false -0.04 -0.04 false false false us-types:perShareItemType decimal The amount of income (loss) from discontinued operations, net of related tax effect, per each diluted share of common stock outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 5 -Section E -Paragraph Question 3 true 37 Diluted Earnings (Loss) Per Share 2 us-gaap_EarningsPerShareDiluted us-gaap true na duration No definition available. false false false false false false false false false false false totallabel true 1 true true false false 0.1 0.1 false false false 2 true true false false -0.01 -0.01 false false false 3 true true false false 0.81 0.81 false false false 4 true true false false 0.52 0.52 false false false us-types:perShareItemType decimal The amount of net income or loss for the period per each share of common stock and dilutive common stock equivalents outstanding during the reporting period. 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