Commitments and Contingencies - Lease Payments on Non-cancelable Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
2019 (three months remaining)	$ 303
2020	1,217
2021	1,232
2022	1,248
2023	1,263
Thereafter	111,757
Total lease payments	117,020
Less: Imputed interest	(94,517)
Lease liability - operating leases	$ 22,503	$ 22,400	$ 0
2019			1,222
2020			1,222
2021			1,222
2022			1,222
2023			1,222
Thereafter			55,689
Total			$ 61,799

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Amount of lessee's undiscounted obligation for lease payments for operating lease.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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