Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2011

Derivative Instruments [Abstract]

Financial Information Related To Hedging Of Net Assets Included In Consolidated Statement Of Earnings

	Year Ended December 31,
	2011		2010		2009
Change in gains (losses) from foreign exchange derivatives	$	(825)	$	5,074	$	(512)
Gain (loss) on net foreign currency assets		(1,181)		(5,243)		408
Net foreign exchange loss	$	(2,006)	$	(169)	$	(104)
	As of
		December 31, 2011		December 31, 2010
Notional balance of outstanding contracts:
Euro/US dollar	€	36,684	€	46,307
Pound/US dollar	£	6,016	£	6,162
Net fair value of outstanding contracts	$	54	$	667

Financial Information Related To Cash Flow Hedges

	As of
	December 31, 2011		December 31, 2010
Net unrealized gains (losses) deferred in other comprehensive income:
Gross	$	8,878	$	(1,522)
Income tax expense (benefit)		2,669		(573)
Net	$	6,209	$	(949)

Financial Information Related To Cash Flow Hedges Of Future Revenues

	As of
		December 31, 2011		December 31, 2010
Notional balance of outstanding contracts versus the dollar	€	85,105	€	73,800
Hedge effectiveness		100%		100%

	Year Ended December 31,
		2011		2010		2009
Net gains and (losses) included in revenue	$	(4,159)	$	(630)	$	603

Forward Contract Amounts Recorded In Consolidated Balance Sheet

	As of
	December 31, 2011		December 31, 2010
Assets:
Other assets	$	9,210	$	3,275
Total	$	9,210	$	3,275