SUMMARY OF QUARTERLY RESULTS OF OPERATIONS (UNAUDITED) (Details 10) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013 Forward starting swap	Sep. 30, 2013 Instruments designated as accounting hedges: Foreign currency forwards	Sep. 30, 2012 Instruments designated as accounting hedges: Foreign currency forwards	Jun. 30, 2013 Instruments designated as accounting hedges: Foreign currency forwards Interim Financial Information	Mar. 31, 2013 Instruments designated as accounting hedges: Foreign currency forwards Interim Financial Information	Dec. 31, 2012 Instruments designated as accounting hedges: Foreign currency forwards Interim Financial Information	Jun. 30, 2012 Instruments designated as accounting hedges: Foreign currency forwards Interim Financial Information	Mar. 31, 2012 Instruments designated as accounting hedges: Foreign currency forwards Interim Financial Information	Dec. 31, 2011 Instruments designated as accounting hedges: Foreign currency forwards Interim Financial Information	Sep. 30, 2013 Instruments designated as accounting hedges: Forward starting swap	Sep. 30, 2012 Instruments designated as accounting hedges: Forward starting swap	Jun. 30, 2013 Instruments designated as accounting hedges: Forward starting swap Interim Financial Information	Mar. 31, 2013 Instruments designated as accounting hedges: Forward starting swap Interim Financial Information	Dec. 31, 2012 Instruments designated as accounting hedges: Forward starting swap Interim Financial Information	Sep. 30, 2013 Instruments not designated as accounting hedges: Foreign currency forwards	Sep. 30, 2012 Instruments not designated as accounting hedges: Foreign currency forwards	Jun. 30, 2013 Instruments not designated as accounting hedges: Foreign currency forwards Interim Financial Information	Mar. 31, 2013 Instruments not designated as accounting hedges: Foreign currency forwards Interim Financial Information	Dec. 31, 2012 Instruments not designated as accounting hedges: Foreign currency forwards Interim Financial Information	Jun. 30, 2012 Instruments not designated as accounting hedges: Foreign currency forwards Interim Financial Information	Mar. 31, 2012 Instruments not designated as accounting hedges: Foreign currency forwards Interim Financial Information	Dec. 31, 2011 Instruments not designated as accounting hedges: Foreign currency forwards Interim Financial Information
Derivative instruments and hedging activities
Notional Principal outstanding derivative instruments	$ 58,400	$ 361,337	$ 382,500	$ 373,591	$ 380,823	$ 393,902	$ 413,633	$ 370,064	$ 358,380	$ 58,415	$ 58,415	$ 58,415	$ 58,415	$ 58,415	$ 2,697	$ 5,945	$ 7,512	$ 7,430	$ 8,511	$ 5,571	$ 3,871	$ 945