Income Taxes	3 Months Ended
Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes Income Taxes The Company, CenStar and Verde Energy USA, Inc. (Verde Corp) are each subject to U.S. federal income tax as corporations. CenStar and Verde Corp will file consolidated tax returns in jurisdictions that allow combined reporting. Spark HoldCo and its subsidiaries, with the exception of CenStar and Verde Corp, are treated as flow-through entities for U.S. federal income tax purposes, and, as such, are generally not subject to U.S. federal income tax at the entity level. Rather, the tax liability with respect to their taxable income is passed through to their members or partners. Accordingly, the Company is subject to U.S. federal income taxation on its allocable share of Spark HoldCo’s net U.S. taxable income. The Company reports federal and state income taxes for its share of the partnership income attributable to its ownership in Spark HoldCo and for the income taxes attributable to CenStar, a C-corporation, which is owned by Spark HoldCo. The income tax liability for the partnership does not accrue to the partnership, but rather the investors are responsible for the income taxes based upon the investor's share of the partnership's income. Net income attributable to the non-controlling interest in CenStar includes the provision for income taxes. The Company accounts for income taxes using the assets and liabilities method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and the tax bases of the assets and liabilities. The Company applies existing tax law and the tax rate that the Company expects to apply to taxable income in the years in which those differences are expected to be recovered or settled in calculating the deferred tax assets and liabilities. Effects of changes in tax rates on deferred tax assets and liabilities are recognized in income in the period of the tax rate enactment. A valuation allowance is recorded when it is not more likely than not that some or all of the benefit from the deferred tax asset will be realized. On December 22, 2017, the President signed the Tax Cuts and Jobs Act (“U.S. Tax Reform”), which enacts a wide range of changes to the U.S. Corporate income tax system. For U.S. federal purposes, a corporate statutory income tax rate of 21% was utilized for the 2018 tax year. The Company remeasured its U.S. federal deferred tax assets and liabilities as of December 31, 2017 using the newly enacted 21% corporate tax rate, the rate expected to be applied when the temporary differences are settled. The Company has not revised any of the 2017 provisional estimates under SAB No. 118 and ASU No 2018-05, but is continuing to gather information and is waiting on further guidance from the IRS, SEC and FASB on U.S. Tax Reform. The Company periodically assesses whether it is more likely than not that it will generate sufficient taxable income to realize its deferred income tax assets. In making this determination, the Company considers all available positive and negative evidence and makes certain assumptions. The Company considers, among other things, its deferred tax liabilities, the overall business environment, its historical earnings and losses, current industry trends, and its outlook for future years. The Company believes it is more likely than not that the deferred tax assets will be utilized. The Company had a net deferred tax asset of approximately $15.6 million related to the step up in tax basis resulting from the purchase by the Company of Spark HoldCo units from NuDevco Retail and NuDevco Retail Holdings (predecessor to Retailco) on the IPO date. In addition, as of March 31, 2018, the Company had a total liability of $32.3 million for the effect of the Tax Receivable Agreement liability, with approximately $5.9 million classified as short-term liability and the remainder as a long-term liability. The Company had a long-term deferred tax asset of approximately $8.2 million related to the Tax Receivable Agreement liability. See Note 14 "Transactions with Affiliates" for further discussion. The effective U.S. federal and state income tax rate for the three months ended March 31, 2018 and 2017 is 13.4% and 17.8%, respectively, with respect to pre-tax income attributable to the Company's stockholders. The lower effective tax rate for the three months ended March 31, 2018 is primarily attributable to the impact of the lower corporate U.S. federal statutory tax rate of 21% enacted for 2018, applied to the mix of earnings between corporate and partnership income. Total income tax benefit for the three months ended March 31, 2018 differed from amounts computed by applying the U.S. federal statutory tax rates to pre-tax income primarily due to state taxes and the impact of permanent differences between book and taxable income, most notably the income attributable to non-controlling interest. The effective tax rate includes a rate benefit attributable to the fact that Spark HoldCo operates as a limited liability company treated as a partnership for federal and state income tax purposes and is not subject to federal and state income taxes. Accordingly, the portion of earnings attributable to non-controlling interest is subject to tax when reported as a component of the non-controlling interest’s taxable income.

12. Income Taxes

Income Taxes

The Company, CenStar and Verde Energy USA, Inc. (Verde Corp) are each subject to U.S. federal income tax as corporations. CenStar and Verde Corp will file consolidated tax returns in jurisdictions that allow combined reporting. Spark HoldCo and its subsidiaries, with the exception of CenStar and Verde Corp, are treated as flow-through entities for U.S. federal income tax purposes, and, as such, are generally not subject to U.S. federal income tax at the entity level. Rather, the tax liability with respect to their taxable income is passed through to their members or partners. Accordingly, the Company is subject to U.S. federal income taxation on its allocable share of Spark HoldCo’s net U.S. taxable income.

The Company reports federal and state income taxes for its share of the partnership income attributable to its ownership in Spark HoldCo and for the income taxes attributable to CenStar, a C-corporation, which is owned by Spark HoldCo. The income tax liability for the partnership does not accrue to the partnership, but rather the investors are responsible for the income taxes based upon the investor's share of the partnership's income. Net income attributable to the non-controlling interest in CenStar includes the provision for income taxes.

The Company accounts for income taxes using the assets and liabilities method. Deferred tax assets and liabilities are recognized for future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and the tax bases of the assets and liabilities. The Company applies existing tax law and the tax rate that the Company expects to apply to taxable income in the years in which those differences are expected to be recovered or settled in calculating the deferred tax assets and liabilities. Effects of changes in tax rates on deferred tax assets and liabilities are recognized in income in the period of the tax rate enactment. A valuation allowance is recorded when it is not more likely than not that some or all of the benefit from the deferred tax asset will be realized.

On December 22, 2017, the President signed the Tax Cuts and Jobs Act (“U.S. Tax Reform”), which enacts a wide range of changes to the U.S. Corporate income tax system. For U.S. federal purposes, a corporate statutory income tax rate of 21% was utilized for the 2018 tax year. The Company remeasured its U.S. federal deferred tax assets and liabilities as of December 31, 2017 using the newly enacted 21% corporate tax rate, the rate expected to be applied when the temporary differences are settled. The Company has not revised any of the 2017 provisional estimates under SAB No. 118 and ASU No 2018-05, but is continuing to gather information and is waiting on further guidance from the IRS, SEC and FASB on U.S. Tax Reform.

The Company periodically assesses whether it is more likely than not that it will generate sufficient taxable income to realize its deferred income tax assets. In making this determination, the Company considers all available positive and negative evidence and makes certain assumptions. The Company considers, among other things, its deferred tax liabilities, the overall business environment, its historical earnings and losses, current industry trends, and its outlook for future years. The Company believes it is more likely than not that the deferred tax assets will be utilized.

The Company had a net deferred tax asset of approximately $15.6 million related to the step up in tax basis resulting from the purchase by the Company of Spark HoldCo units from NuDevco Retail and NuDevco Retail Holdings (predecessor to Retailco) on the IPO date. In addition, as of March 31, 2018, the Company had a total liability of $32.3 million for the effect of the Tax Receivable Agreement liability, with approximately $5.9 million classified as short-term liability and the remainder as a long-term liability. The Company had a long-term deferred tax asset of approximately $8.2 million related to the Tax Receivable Agreement liability. See Note 14 "Transactions with Affiliates" for further discussion.

The effective U.S. federal and state income tax rate for the three months ended March 31, 2018 and 2017 is 13.4% and 17.8%, respectively, with respect to pre-tax income attributable to the Company's stockholders. The lower effective tax rate for the three months ended March 31, 2018 is primarily attributable to the impact of the lower corporate U.S. federal statutory tax rate of 21% enacted for 2018, applied to the mix of earnings between corporate and partnership income.

Total income tax benefit for the three months ended March 31, 2018 differed from amounts computed by applying the U.S. federal statutory tax rates to pre-tax income primarily due to state taxes and the impact of permanent differences between book and taxable income, most notably the income attributable to non-controlling interest. The effective tax rate includes a rate benefit attributable to the fact that Spark HoldCo operates as a limited liability company treated as a partnership for federal and state income tax purposes and is not subject to federal and state income taxes. Accordingly, the portion of earnings attributable to non-controlling interest is subject to tax when reported as a component of the non-controlling interest’s taxable income.