Derivative Instruments Gain (Loss) Hedging Relationship, Income Statement (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Not Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Interest income and other, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income on derivative	$ 927	$ (2,586)	$ 1,430	$ (637)
Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in other comprehensive Income (OCI) on derivative (effective portion)	973	(2,801)	556	(2,906)
Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | Interest income and other, net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in income derivative (Ineffective portion and amount excluded from effectiveness testing)	546	383	1,703	1,496
Designated as Hedging Instrument [Member] | Foreign Exchange Contract [Member] | Cash Flow Hedging [Member] | General and administrative [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) reclassified from accumulated OCI into income (effective portion)	$ (985)	$ 54	$ (3,700)	$ 120
Maximum [Member] | Foreign Exchange Contract [Member] | Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative maturity period (days/months)			12 months
Maximum [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative maturity period (days/months)	90 days