Income Taxes - Income Tax Expense Details (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current expense:
Federal									$ 17,661	$ 12	$ (81)
State									8,071	274	56
Total current expense									25,732	286	(25)
Deferred expense:
Federal									85,296	23,395	14,674
State									25,451	(427)	9,738
Total provision for deferred income taxes									110,747	22,968	24,412
Total provision for income taxes	$ 50,705	$ 44,724	$ 26,894	$ 14,156	$ 5,346	$ 5,545	$ 6,293	$ 6,070	$ 136,479	$ 23,254	$ 24,387