Fee and Other Income (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Fee and Other Income [Abstract]
Tenant cleaning fees	$ 15,647	$ 13,613	$ 46,479	$ 40,733
Management and leasing fees	4,361	3,555	15,456	16,075
Lease termination fees	4,803	2,301	12,478	10,112
Other income	12,195	12,797	37,826	37,918
Total Fee and Other Income	37,006	32,266	112,239	104,838
Management fee income from Interstate Properties	$ 195	$ 192	$ 586	$ 584