Real Estate - Intangibles (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of in-place lease valuation
In-place lease valuation (above market)	$ 44,012	$ 44,012
In-place lease valuation (above market) - accumulated amortization	(34,011)	(33,322)
In-place lease valuation (above market), net	10,001	10,690
Ground leasehold interest (below market)	2,254	2,254
Ground leasehold interest (below market) - accumulated amortization	(170)	(164)
Ground leasehold interest (below market), net	2,084	2,090
Intangible assets, net	12,085	12,780
In-place lease valuation (below market)	(68,335)	(67,622)
Land Leasehold interest (above market)	(3,072)	(3,073)
In-place lease valuation & land leasehold interest - accumulated amortization	40,420	38,890
Intangible liabilities, net	(30,987)	(31,805)
Tenant origination and absorption cost	749,743	744,773
Tenant origination and absorption cost - accumulated amortization	(371,971)	(354,379)
Tenant origination and absorption cost, net	$ 377,772	$ 390,394