Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount
Expected U.S. federal income taxes at statutory rate	$ (76,574,000)	$ (53,496,000)	$ (57,511,000)
Impact of 2017 Tax Cuts and Jobs Act	0	0	9,303,000
Loss attributable to non-controlling interests	52,496,000	41,024,000	52,607,000
State taxes	(2,945,000)	(2,363,000)	(553,000)
Valuation allowance	18,039,000	14,771,000	(3,911,000)
Effect due to LLC flow-through structure	10,004,000	0	0
Other	(1,020,000)	65,000	65,000
Income tax expense	$ 0	$ 0	$ 0
Percent
Expected U.S. federal income taxes at statutory rate	21.00%	21.00%	35.00%
Impact of 2017 Tax Cuts and Jobs Act	0.00%	0.00%	(5.70%)
Loss attributable to non-controlling interests	(14.40%)	(16.10%)	(32.00%)
State taxes	0.80%	0.90%	0.30%
Valuation allowance	(4.90%)	(5.80%)	2.40%
Other	0.20%	0.00%	0.00%
Effect due to LLC flow-through structure	(2.70%)	0.00%	0.00%
Income tax expense, Percent	0.00%	0.00%	0.00%