CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Statement - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 36,093	$ (24,896)	$ 57,756	$ (31,066)
Share of other comprehensive income (loss) of equity method investments	0	0	(31)	0
Reclassification adjustment for sale of equity method investments	6	(1)	6	81
Total comprehensive income (loss)	$ 36,099	$ (24,897)	$ 57,731	$ (30,985)