Leases - Future Minimum Lease Payments on Ground Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Leases [Abstract]
Remainder of 2019	$ 380
2020	1,518
2021	1,518
2022	1,518
2023	1,518
Thereafter	68,298
Total undiscounted cash flows	74,750
Present value discount	(45,395)
Ground lease liabilities	$ 29,355
2019		$ 1,518
2020		1,518
2021		1,518
2022		1,518
2023		1,518
Thereafter		68,298
Future minimum lease payments to be paid		$ 75,888

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

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Amount of lessee's undiscounted obligation for lease payments for operating lease having an initial or remaining lease term in excess of one year due in remainder of fiscal year following latest fiscal year.

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

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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