Fee and Other Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Fee And Other Income
BMS cleaning fees	$ 26,429	$ 24,532	$ 75,925	$ 68,656
Management and leasing fees	2,330	1,935	7,382	5,694
Lease termination fees	991	1,819	5,947	7,123
Other income	3,542	2,357	8,958	6,561
Fee and other income	33,292	30,643	98,212	88,034
Interstate Properties
Fee And Other Income
Management and leasing fees	$ 125	$ 128	$ 377	$ 390