FAIR VALUE MEASUREMENTS (Details) (Recurring basis, USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Quoted Prices in Active Markets (Level 1)
Fair value measurements
Assets measured at fair value	$ 80,806	$ 1,755
Quoted Prices in Active Markets (Level 1) | Money market funds
Fair value measurements
Assets measured at fair value	80,806	1,755
Significant Other Observable Inputs (Level 2)
Fair value measurements
Assets measured at fair value	363	363
Liabilities measured at fair value	5,651	11,142
Significant Other Observable Inputs (Level 2) | Interest rate derivative
Fair value measurements
Liabilities measured at fair value	5,651	11,142
Significant Other Observable Inputs (Level 2) | Certificate of deposit
Fair value measurements
Assets measured at fair value	363	363
Total
Fair value measurements
Assets measured at fair value	81,169	2,118
Liabilities measured at fair value	5,651	11,142
Total | Interest rate derivative
Fair value measurements
Liabilities measured at fair value	5,651	11,142
Total | Certificate of deposit
Fair value measurements
Assets measured at fair value	363	363
Total | Money market funds
Fair value measurements
Assets measured at fair value	80,806	1,755
Total | Restricted cash
Fair value measurements
Assets measured at fair value	$ 78,000