Income Taxes - Tax Rate Reconciliation Table (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Income (loss) before income taxes	$ 821,172	$ 689,588	$ 677,462
Statutory tax rate	0.00%	0.00%	0.00%
Adjustments resulting from:
U.S. federal tax reform	$ 0	$ 0	$ (87,306)
Federal taxes on income	0	0	0
State taxes on income (net of federal benefit) and Texas margin tax expense (benefit)	5,140	2,946	4,866
Income tax expense (benefit)	$ 13,472	$ 58,934	$ (59,923)
Effective tax rate	2.00%	9.00%	(9.00%)
Pre-Acquisition From Anadarko [Member]
Adjustments resulting from:
Federal taxes on income	$ 8,332	$ 54,243	$ 22,353
State taxes on income (net of federal benefit) and Texas margin tax expense (benefit)	$ 0	$ 1,745	$ 164

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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