SEGMENT REPORTING (Details 2) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Assets for each of the reportable segments
Total assets	$ 4,420,885	$ 4,451,492
Operating segment | Core properties
Assets for each of the reportable segments
Total assets	3,725,911	3,754,000
Operating segment | Non-core properties
Assets for each of the reportable segments
Total assets	604,200	592,386
Reconciling items
Assets for each of the reportable segments
Total assets	$ 90,774	$ 105,106