Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amount
Statutory U.S. Federal Income Tax Rate	$ (126,595)	$ 12,534	$ 230,721
Net Effect of State Income Taxes	(32,336)	1,333	60,814
Non-Controlling Interest	(11,556)	(23,662)	(18,181)
Uncertain Tax Positions	375	0	(4,265)
Accrual to Tax Return Reconciliation	13	603	3,028
Effect of Equity Compensation	4,311	8,771	0
Effect of Change in State Valuation Allowance	(2,004)	33,238	(22,684)
Effect of Change in Federal Valuation Allowance	48	(2,640)	(18,110)
Other Deferred Adjustments	1,166	(1,691)	5,957
Effect of Federal and State Rate Reductions	(1,450)	(3,842)	(27,429)
Effect of Federal Tax Credits	(6,284)	2,881	1,208
Other	225	211	4,498
Income Tax (Benefit) Expense / Effective Rate	$ (174,087)	$ 27,736	$ 215,557
Percent
Statutory U.S. Federal Income Tax Rate	21.00%	21.00%	21.00%
Net Effect of State Income Taxes	5.50%	2.20%	5.60%
Non-Controlling Interest	1.90%	(39.60%)	(1.70%)
Uncertain Tax Positions	(0.10%)	0.00%	(0.40%)
Accrual to Tax Return Reconciliation	0.00%	1.00%	0.30%
Effect of Equity Compensation	(0.70%)	14.70%	0.00%
Effect of Change in State Valuation Allowance	0.30%	55.60%	(2.10%)
Effect of Change in Federal Valuation Allowance	0.00%	(4.40%)	(1.70%)
Other Deferred Adjustments	(0.20%)	(2.80%)	0.60%
Effect of Federal and State Rate Reductions	0.20%	(6.40%)	(2.50%)
Effect of Federal Tax Credits	1.00%	4.80%	0.10%
Other	0.00%	0.40%	0.40%
Income Tax (Benefit) Expense / Effective Rate	28.90%	46.50%	19.60%

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