INCOME TAXES	9 Months Ended
INCOME TAXES	Sep. 30, 2017
income tax [Line Items]
Income Tax Disclosure [Text Block]	INCOME TAXES The Company files consolidated federal income tax returns which include Consolidated SCE&G, and the Company and its subsidiaries file various applicable state and local income tax returns. The IRS has completed examinations of the Company’s federal returns through 2004, and the Company’s federal returns through 2007 are closed for additional assessment. The IRS is currently examining SCANA's open federal returns through 2015 as a result of claims discussed below. With few exceptions, the Company, including Consolidated SCE&G, is no longer subject to state and local income tax examinations by tax authorities for years before 2010. During 2013 and 2014, SCANA amended certain of its income tax returns to claim additional tax-defined research and experimentation deductions (under IRC Section 174) and credits (under IRC Section 41) and to reflect related impacts on other items such as domestic production activities deductions (under IRC Section 199). SCANA also made similar claims in filing its original 2013 and 2014 returns in 2014 and 2015, respectively. In 2016 and 2017, SCANA claimed significant research and experimentation deductions and credits (offset by reductions in its domestic production activities deductions), related to the design and construction activities of the New Units, in its 2015 and 2016 income tax returns. These claims followed the issuance of final IRS regulations in 2014 regarding such treatment with respect to expenditures related to the design and construction of pilot models. The IRS examined the claims in the amended returns, and as the examination progressed without resolution, the Company and Consolidated SCE&G evaluated and recorded adjustments to unrecognized tax benefits; however, none of these changes materially affected the Company's and Consolidated SCE&G's effective tax rate. In October 2016, the examination of the amended tax returns progressed to the IRS Office of Appeals. In addition, the IRS has begun an examination of SCANA's 2013 through 2015 income tax returns. These income tax deductions and credits are considered to be uncertain tax positions, and under relevant accounting guidance, estimates of the amounts of related tax benefits which may not be sustained upon examination by the taxing authorities are required to be recorded as unrecognized tax benefits in the financial statements. As of September 30, 2017, the Company and Consolidated SCE&G have recorded an unrecognized tax benefit of $457 million ($402 million net of the impact of state deductions on federal returns and net of receivables related to the uncertain tax positions). If recognized, $17 million of the tax benefit would affect the Company’s and Consolidated SCE&G's effective tax rates (see discussion below regarding deferral of benefits related to 2015 forward). These unrecognized tax benefits are not expected to increase significantly within the next 12 months, although other uncertain tax positions may be identified or taken, particularly with respect to the abandonment of the construction of the New Units during 2017. It is reasonably possible that these known unrecognized tax benefits may decrease by $457 million within the next 12 months. No other material changes in the status of the Company’s or Consolidated SCE&G's tax positions have occurred through September 30, 2017. In connection with the research and experimentation deduction and credit claims reflected on the 2015 and 2016 income tax returns and similar claims made in determining 2017’s taxable income, and under the terms of an order of the SCPSC, the Company and Consolidated SCE&G have recorded regulatory assets for estimated foregone domestic production activities deductions, offset by estimated tax credits, and expect that such (net) deferred costs, along with any interest (see below) and other related deferred costs, will be recoverable through customer rates in future years (see condensed consolidated Note 2). SCE&G's current customer rates reflect the availability of domestic production activities deductions. Also under the terms of an order of the SCPSC, estimated interest expense accrued with respect to the unrecognized tax benefits related to the research and experimentation deductions in the 2015 and 2016 income tax returns has been deferred as a regulatory asset and is expected to be recoverable through customer rates in future years. See also condensed consolidated Note 2. Otherwise, the Company and Consolidated SCE&G recognize interest accrued related to unrecognized tax benefits within interest expense or interest income and recognize tax penalties within other expenses. Amounts recorded for such interest income, interest expense or tax penalties have not been material for any period presented. Effective January 1, 2017, the State of North Carolina reduced its corporate income tax rate from 4% to 3%. During the second quarter of 2017, the State of North Carolina passed legislation that will lower the state corporate income tax rate from 3% to 2.5% effective January 1, 2019. In connection with these changes in tax rates, related state deferred taxes were remeasured, with the change in their balances being credited to a regulatory liability. These changes in income tax rates did not and are not expected to have a material impact on the Company’s financial position, results of operations or cash flows.
SCEG
income tax [Line Items]
Income Tax Disclosure [Text Block]	INCOME TAXES The Company files consolidated federal income tax returns which include Consolidated SCE&G, and the Company and its subsidiaries file various applicable state and local income tax returns. The IRS has completed examinations of the Company’s federal returns through 2004, and the Company’s federal returns through 2007 are closed for additional assessment. The IRS is currently examining SCANA's open federal returns through 2015 as a result of claims discussed below. With few exceptions, the Company, including Consolidated SCE&G, is no longer subject to state and local income tax examinations by tax authorities for years before 2010. During 2013 and 2014, SCANA amended certain of its income tax returns to claim additional tax-defined research and experimentation deductions (under IRC Section 174) and credits (under IRC Section 41) and to reflect related impacts on other items such as domestic production activities deductions (under IRC Section 199). SCANA also made similar claims in filing its original 2013 and 2014 returns in 2014 and 2015, respectively. In 2016 and 2017, SCANA claimed significant research and experimentation deductions and credits (offset by reductions in its domestic production activities deductions), related to the design and construction activities of the New Units, in its 2015 and 2016 income tax returns. These claims followed the issuance of final IRS regulations in 2014 regarding such treatment with respect to expenditures related to the design and construction of pilot models. The IRS examined the claims in the amended returns, and as the examination progressed without resolution, the Company and Consolidated SCE&G evaluated and recorded adjustments to unrecognized tax benefits; however, none of these changes materially affected the Company's and Consolidated SCE&G's effective tax rate. In October 2016, the examination of the amended tax returns progressed to the IRS Office of Appeals. In addition, the IRS has begun an examination of SCANA's 2013 through 2015 income tax returns. These income tax deductions and credits are considered to be uncertain tax positions, and under relevant accounting guidance, estimates of the amounts of related tax benefits which may not be sustained upon examination by the taxing authorities are required to be recorded as unrecognized tax benefits in the financial statements. As of September 30, 2017, the Company and Consolidated SCE&G have recorded an unrecognized tax benefit of $457 million ($402 million net of the impact of state deductions on federal returns and net of receivables related to the uncertain tax positions). If recognized, $17 million of the tax benefit would affect the Company’s and Consolidated SCE&G's effective tax rates (see discussion below regarding deferral of benefits related to 2015 forward). These unrecognized tax benefits are not expected to increase significantly within the next 12 months, although other uncertain tax positions may be identified or taken, particularly with respect to the abandonment of the construction of the New Units during 2017. It is reasonably possible that these known unrecognized tax benefits may decrease by $457 million within the next 12 months. No other material changes in the status of the Company’s or Consolidated SCE&G's tax positions have occurred through September 30, 2017. In connection with the research and experimentation deduction and credit claims reflected on the 2015 and 2016 income tax returns and similar claims made in determining 2017’s taxable income, and under the terms of an order of the SCPSC, the Company and Consolidated SCE&G have recorded regulatory assets for estimated foregone domestic production activities deductions, offset by estimated tax credits, and expect that such (net) deferred costs, along with any interest (see below) and other related deferred costs, will be recoverable through customer rates in future years (see condensed consolidated Note 2). SCE&G's current customer rates reflect the availability of domestic production activities deductions. Also under the terms of an order of the SCPSC, estimated interest expense accrued with respect to the unrecognized tax benefits related to the research and experimentation deductions in the 2015 and 2016 income tax returns has been deferred as a regulatory asset and is expected to be recoverable through customer rates in future years. See also condensed consolidated Note 2. Otherwise, the Company and Consolidated SCE&G recognize interest accrued related to unrecognized tax benefits within interest expense or interest income and recognize tax penalties within other expenses. Amounts recorded for such interest income, interest expense or tax penalties have not been material for any period presented. Effective January 1, 2017, the State of North Carolina reduced its corporate income tax rate from 4% to 3%. During the second quarter of 2017, the State of North Carolina passed legislation that will lower the state corporate income tax rate from 3% to 2.5% effective January 1, 2019. In connection with these changes in tax rates, related state deferred taxes were remeasured, with the change in their balances being credited to a regulatory liability. These changes in income tax rates did not and are not expected to have a material impact on the Company’s financial position, results of operations or cash flows.