Equity Method Investments - Activity Related to Equity Method Investments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity Method Investments
Balance at beginning of period	$ 163,181	$ 86,077	$ 129,524
Contributions	9,338	77,263	57,039
Distributions	(17,453)	(1,296)	0
Earnings (loss) on equity method investments	80,496	1,137	(100,486)
Reclassification of accumulated losses	9,400	0	0
Sale of investment	(244,962)	0	0
Balance at end of period	0	163,181	86,077
Constitution
Equity Method Investments
Balance at beginning of period	0	732	96,850
Contributions	725	500	4,350
Distributions	0	0	0
Earnings (loss) on equity method investments	(10,125)	(1,232)	(100,468)
Reclassification of accumulated losses	9,400	0	0
Sale of investment	0	0	0
Balance at end of period	0	0	732
Meade
Equity Method Investments
Balance at beginning of period	163,181	85,345	32,674
Contributions	8,613	76,763	52,689
Distributions	(17,453)	(1,296)	0
Earnings (loss) on equity method investments	90,621	2,369	(18)
Reclassification of accumulated losses	0	0	0
Sale of investment	(244,962)	0	0
Balance at end of period	$ 0	$ 163,181	$ 85,345