Revenues - Summary of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation Of Revenue [Abstract]
Rental income	$ 163,405	$ 155,390
Tenant reimbursement income	14,246	12,852
Fee income:
Property management	1,502	1,610
Asset management	1,610	2,293
Acquisition, disposition and leasing		5,320
Other	353	333
Total fee income	3,465	9,556
Lease termination income	28	66
Other income	3,127	3,372
Total fee and other income	6,620	12,994
Total revenues	$ 184,271	$ 181,236