Intangible Assets and Liabilities - Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 1,674	$ 1,674
Total intangible assets	177,146	189,164
In-Place  Leases
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	222,779	212,413
Finite-lived intangible assets, net	134,924	145,290
Above-Market Rents
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	35,131	33,548
Finite-lived intangible assets, net	23,377	24,960
Below-Market Ground Lease
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	1,242	1,173
Finite-lived intangible assets, net	$ 17,171	$ 17,240