Acquired Lease Intangibles - Impact on Consolidated Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization/accretion of above/below-market leases	$ 4,256	$ 4,120
Rental revenues | Tenant Lease
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization/accretion of above/below-market leases	4,259	4,124
Office parking and other income | Above Market Ground Leases
Acquired Finite-Lived Intangible Assets [Line Items]
Amortization/accretion of above/below-market leases	$ (3)	$ (4)