Income taxes	3 Months Ended
Mar. 31, 2020
Income Tax Disclosure [Abstract]
Income taxes	Income taxesThe Company’s and the Utilities’ effective tax rates (combined federal and state income tax rates) were 15% and 18%, respectively, for the three months ended March 31, 2020. These rates differed from the combined statutory rates, due primarily to the Utilities’ 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 tax benefits derived from the low income housing tax credit investments and the non-taxability of the bank-owned life insurance income. The Company’s and the Utilities’ effective tax rates were 20% and 22%, respectively, for the three months ended March 31, 2019.

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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