Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Income taxes	Income taxes Our effective tax rate for the three and nine months ended September 30, 2020 was 14.0% and 19.6%, respectively, compared to 25.4% and 24.6%, respectively, for the same periods in 2019. Our effective tax rate differs from the federal statutory rate primarily due to benefits associated with federal energy efficient home credits partially offset by state income tax expense. Income tax expense for the three and nine months ended September 30, 2020 includes benefits of $53.2 million and $58.0 million, respectively, associated with the extension of federal energy efficient homes tax credits, including to homes closed in prior open tax years. This provision was extended to apply to homes closed through December 31, 2020. At September 30, 2020 and December 31, 2019, we had deferred tax assets, net of deferred tax liabilities and valuation allowance, of $80.8 million and $170.1 million, respectively. The accounting for deferred taxes is based upon estimates of future results. Differences between estimated and actual results could result in changes in the valuation of deferred tax assets that could have a material impact on our consolidated results of operations or financial position. Changes in existing tax laws could also affect actual tax results and the realization of deferred tax assets over time. Unrecognized tax benefits represent the difference between tax positions taken or expected to be taken in a tax return and the benefits recognized for financial statement purposes. We had $27.3 million and $40.3 million of gross unrecognized tax benefits at September 30, 2020 and December 31, 2019, respectively. Additionally, we had accrued interest and penalties of $2.3 million and $6.5 million at September 30, 2020 and December 31, 2019, respectively.

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.