Intangible Assets and Liabilities - Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Intangible Assets [Line Items]
Intangible assets, total cost	$ 163,336	$ 177,581
Intangible assets, accumulated amortization	(87,666)	(92,730)
Intangible assets, net	75,670	84,851
Acquired lease intangibles, net	20,605	22,263
In-place lease value
Intangible Assets [Line Items]
Intangible assets, total cost	153,328	167,357
Intangible assets, accumulated amortization	(79,024)	(84,123)
Intangible assets, net	74,304	83,234
Tenant relationship value
Intangible Assets [Line Items]
Intangible assets, total cost	5,142	5,268
Intangible assets, accumulated amortization	(4,775)	(4,815)
Intangible assets, net	367	453
Above market leases acquired
Intangible Assets [Line Items]
Intangible assets, total cost	4,866	4,956
Intangible assets, accumulated amortization	(3,867)	(3,792)
Intangible assets, net	999	1,164
Below market leases acquired
Intangible Assets [Line Items]
Acquired lease intangibles, gross	43,302	44,757
Acquired lease intangibles, accumulated amortization	(22,697)	(22,494)
Acquired lease intangibles, net	$ 20,605	$ 22,263