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Commitments and Contingencies - Minimum Commitment Under Ground Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Minimum commitment under our ground leases
2020	$ 5,641
2021	5,641
2022	5,642
2023	5,662
2024	5,662
Thereafter	286,385
Total	314,633
Present value discount	(216,233)
Ground lease liabilities	$ 98,400	$ 98,349
Minimum commitment under our ground leases
2019			$ 5,154
2020			5,154
2021			5,154
2022			5,154
2023			5,154
Thereafter			233,619
Total			$ 259,389