Real Estate and Lease Intangibles - Summary of the Effect of the Amortization for Above and Below Market Ground and Retail Lease Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total amortization of above/below market lease intangibles	$ (1,098)	$ (1,012)	$ (3,294)	$ (2,729)
Ground Lease [Member] | Property and Maintenance [Member]
Total amortization of above/below market lease intangibles	(1,116)	(1,092)	(3,348)	(3,253)
Retail Lease [Member] | Rental Income [Member]
Total amortization of above/below market lease intangibles	$ 18	$ 80	$ 54	$ 524