Significant Accounting Policies - Schedule of Intangible Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross	$ 92,856	$ 88,859
Below-market leases, gross	(50,315)	(45,798)
Finite-lived intangible assets (liabilities), gross	42,541	43,061
Below-market lease, accumulated amortization	22,433	21,190
Finite-lived intangible assets (liabilities), accumulated amortization	(47,750)	(47,175)
Below-market leases, net	(27,882)	(24,608)
Total	(5,209)	(4,114)
In-place leases
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross	89,014	85,026
Finite-lived intangible assets, accumulated amortization	(66,466)	(64,668)
Finite-lived intangible assets, net	22,548	20,358
Above-market leases
Finite-Lived Intangible Assets
Finite-lived intangible assets, gross	3,842	3,833
Finite-lived intangible assets, accumulated amortization	(3,717)	(3,697)
Finite-lived intangible assets, net	$ 125	$ 136