Leases - Minimum Annual Rental Payments Under Operating Leases (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Lessee Lease Description [Line Items]
October 1, 2019 to December 31, 2019	$ 1,381
2020	5,156
2021	5,143
2022	5,053
2023	4,363
Thereafter	432,813
Total	453,909
Less: Discount	(358,032)
Total lease liability	$ 95,877
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesAndOtherLiabilities
Office Lease Future Minimum Rent
Lessee Lease Description [Line Items]
October 1, 2019 to December 31, 2019	$ 852
2020	2,806
2021	2,704
2022	2,561
2023	1,871
Thereafter	10,644
Total	21,438
Less: Discount	(3,091)
Total lease liability	$ 18,347
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesAndOtherLiabilities
Ground Lease Future Minimum Rent
Lessee Lease Description [Line Items]
October 1, 2019 to December 31, 2019	$ 529
2020	2,350
2021	2,439
2022	2,492
2023	2,492
Thereafter	422,169
Total	432,471
Less: Discount	(354,941)
Total lease liability	$ 77,530
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesAndOtherLiabilities