Net Income (Loss) Per Share - EPS Reconciliation (Details) - USD ($) $ / shares in Units, $ 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
Earnings Per Share [Abstract]
Net income (loss) from continuing operations available to common stockholders - Basic	$ 492,556	$ (13,753)	$ (57,635)	$ (41,387)	$ 30,448	$ 24,799	$ 28,277	$ 212,608	$ 381,112	$ 295,804	$ (66,279)
Plus (less): effect of participating securities									8,619	7,824	0
Net income (loss) available to common stockholders									389,731	303,628	(66,279)
Less: effect of participating securities									(8,619)	(7,824)	0
Net income (loss) from continuing operations available to common stockholders - Diluted									381,112	295,804	(66,279)
Net loss from discontinued operations available to common stockholders - Basic	$ (995)	$ (2,193)	$ (4,462)	$ (2,017)	$ (12,197)	$ (469)	$ 4,681	$ (3,455)	(9,667)	(11,312)	(12,800)
Plus (less): effect of participating securities									0	0	0
Net loss available to common stockholders									(9,667)	(11,312)	(12,800)
Less: effect of participating securities									0	0	0
Net loss from discontinued operations available to common stockholders - Diluted									(9,667)	(11,312)	(12,800)
Net income (loss) available to common stockholders - Basic									371,659	284,783	(79,079)
Plus (less): effect of participating securities									8,405	7,533	0
Net income (loss) available to common stockholders									380,064	292,316	(79,079)
Less: effect of participating securities									(8,405)	(7,533)	0
Net income (loss) available to common stockholders - Diluted									$ 371,659	$ 284,783	$ (79,079)
Weighted-average shares used to compute basic net income (loss) per share (in shares)									38,288,610	37,687,552	38,731,015
Adjustment to reflect conversion of convertible notes (in shares)									3,589,065	5,416,043	0
Adjustment to reflect stock appreciation right conversions (in shares)									443,305	550,125	0
Weighted-average shares used to compute diluted net income (loss) per share (in shares)									42,320,980	43,653,720	38,731,015
Net income (loss) per share available to common stockholders - Diluted
Continuing operations (in dollars per share)	$ 11.52	$ (0.35)	$ (1.52)	$ (1.11)	$ 0.66	$ 0.55	$ 0.67	$ 5.38	$ 9.01	$ 6.78	$ (1.71)
Discontinued operations (in dollars per share)	(0.03)	(0.06)	(0.12)	(0.05)	(0.33)	(0.01)	0.11	(0.09)	(0.25)	(0.30)	(0.33)
Diluted net income (loss) (in dollars per share)	$ 11.50	$ (0.41)	$ (1.64)	$ (1.16)	$ 0.40	$ 0.53	$ 0.78	$ 5.30	$ 8.78	$ 6.52	$ (2.04)