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Income Taxes - Reconciliation of Statutory Federal Income Tax Amount (Details) - USD ($) | 3 Months Ended | 12 Months Ended
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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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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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