Income Taxes	6 Months Ended
Income Taxes	Jun. 30, 2021
Income Tax Disclosure [Abstract]
Income taxes	Income taxesOur effective tax rate for the three and six months ended June 30, 2021 was 21.3% and 21.9%, respectively, compared to 23.7% and 23.4%, respectively, for the same periods in 2020. Our effective tax rate for each of these periods differs from the federal statutory rate primarily due to state income tax expense, partially offset by benefits associated with federal energy efficient home credits. The effective tax rate for 2021 also reflects a reduction in valuation allowances relating to projected utilization of certain state net operating loss carryforwards. At June 30, 2021 and December 31, 2020, we had net deferred tax assets of $27.9 million and $32.7 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 $35.1 million and $30.9 million of gross unrecognized tax benefits at June 30, 2021 and December 31, 2020, respectively. Additionally, we had accrued interest and penalties of $3.3 million and $2.8 million at June 30, 2021 and December 31, 2020, 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.