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Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jan. 01, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Gain on settlement of contingent consideration—related party	$ 0	$ 0	$ 64,870	$ 0
Related party liabilities	128,513		128,513		$ 197,351	$ 178,540
Related party assets	95,615		95,615		79,850	61,039
Great Park Venture
Related Party Transaction [Line Items]
Related party assets	1,800		1,800			1,800
Accounting Standards Update 2016-02
Related Party Transaction [Line Items]
Related party liabilities					18,811
Prepaid rent					6,000
Related party assets					$ 18,811
Affiliated Entity
Related Party Transaction [Line Items]
Prepaid rent	0		0			(5,972)
Loan Reimbursement Agreement \| Affiliated Entity
Related Party Transaction [Line Items]
Related party liabilities	$ 102,692		$ 102,692			$ 102,692