DERIVATIVES AND FAIR VALUE MEASUREMENTS (Schedule of Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011
Assets
Money market funds	$ 174,570
Foreign currency hedge contracts	3,828
Assets, Fair Value Disclosure, Total	178,398
Liabilities
Foreign currency hedge contracts	3,131
Liabilities, Fair Value Disclosure	3,131
Fair Value, Inputs, Level 1
Assets
Money market funds	174,570
Foreign currency hedge contracts	0
Assets, Fair Value Disclosure, Total	174,570
Liabilities
Foreign currency hedge contracts	0
Liabilities, Fair Value Disclosure	0
Fair Value, Inputs, Level 2
Assets
Money market funds	0
Foreign currency hedge contracts	3,828
Assets, Fair Value Disclosure, Total	3,828
Liabilities
Foreign currency hedge contracts	3,131
Liabilities, Fair Value Disclosure	3,131
Fair Value, Inputs, Level 3
Assets
Money market funds	0
Foreign currency hedge contracts	0
Assets, Fair Value Disclosure, Total	0
Liabilities
Foreign currency hedge contracts	0
Liabilities, Fair Value Disclosure	$ 0