Income taxes	3 Months Ended
Mar. 31, 2019
Income Tax Disclosure [Abstract]
Income taxes	Income taxesThe Company’s and the Utilities’ effective tax rates were 20% and 22%, respectively, for the three months ended March 31, 2019. These rates differed from statutory rates, due primarily to the tax effect of the state income tax deduction and the amortization of excess deferred income taxes related to the provision in the Tax Act that lowered the federal income tax rate from 35% to 21%. The Company’s and the Utilities’ effective tax rate were 24% and 25%, respectively, for the three months ended March 31, 2018.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

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