PREPAID EXPENSES AND OTHER ASSETS (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Prepaid expenses and other assets
Deposits	$ 796	$ 902
Prepaid expenses	3,563	4,349
Other	3,786	3,068
Total prepaid expenses and other assets	99,458	127,025
Tenant leases | Above-market tenant leases, net
Prepaid expenses and other assets
Net carrying amount	89,407	116,675
Ground leases | Below-market tenant leases, net
Prepaid expenses and other assets
Net carrying amount	$ 1,906	$ 2,031