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Income Taxes - Reconciliation of Statutory Federal Income Tax Amount (Details) - USD ($)	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
Income Tax Disclosure [Abstract]
Income (loss) before federal income taxes									$ (2,009,921,000)	$ 430,491,000	$ 436,961,000
Expected income tax at statutory rate									(422,083,000)	90,403,000	152,936,000
State income taxes									(28,316,000)	(511,000)	2,299,000
Other differences									3,372,000	1,078,000	5,731,000
Remeasurement due to Tax Cut and Jobs Act									0	0	190,034,000
Change in valuation allowance due to current year activity									439,464,000	(91,039,000)	(158,704,000)
Change in valuation allowance due to Tax Cuts and Jobs Act									0	0	(190,487,000)
Total income tax (benefit) expense provision	$ 315,815,000	$ (144,047,000)	$ (179,331,000)	$ 0	$ 0	$ 0	$ 0	$ (69,000)	$ (7,563,000)	$ (69,000.0)	$ 1,809,000

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Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Tax Cuts and Jobs Act of 2017, Amount

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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