Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes — Deferred tax assets and liabilities are recorded based on the difference between the financial statement and tax bases of assets and liabilities at the enacted tax rates. We review our deferred tax assets regularly for recoverability. At September 30, 2020 and 2019, and December 31, 2019, we determined that we did not need a valuation allowance on our gross deferred tax assets. Although realization of the deferred tax assets is not assured, management believes that it is more likely than not the deferred tax assets will be realized based on our expectation that we will be able to fully utilize the deductions that are ultimately recognized for tax purposes. For the nine months ended September 30, 2020, there have been no material changes in our reserve for uncertain tax positions. The effective tax rate for the three and nine months ended September 30, 2020, was 20.4% and 20.7%, respectively, compared to 16.5% and 24.0% for the same periods last year. For the three months ended September 30, 2019, the lower effective rate was due primarily to renewable energy investment tax credits and the vesting of employee stock based compensation awards. For the nine months ended September 30, 2019, the higher effective rate was due primarily to the reversal of certain tax credits, unrelated to those impacting the quarter, and other tax benefits previously recognized from certain renewable energy investments, where the sponsor pled guilty to fraud through these investments and the tax credits and other benefits related to those investments were not valid. See Note 5 – Income Taxes in our 2019 Annual Report to Shareholders for further discussion.

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.