Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2011

Fair Value Disclosures [Abstract]

Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis Table

							Fair Value Measurements as of December 31, 2011
	Carrying Amount		Total Fair Value		Cash		Level 1		Level 2		Level 3
Measured on a recurring basis:
Assets:
Cash	$	47,502	$	47,502	$	47,502	$	—	$	—	$	—
Cash equivalents	68,803		68,803		—		40,793		28,010		—
Short-term—marketable securities	46,006		46,006		—		7,501		38,505		—
Non-Qualified Deferred Compensation Plan funds	3,635		3,635		—		3,635		—		—
Total	$	165,946	$	165,946	$	47,502	$	51,929	$	66,515	$	—
Liabilities:
Earnout payment liability	$	890	$	890	$	—	$	—	$	—	$	890
Non-Qualified Deferred Compensation Plan	3,635		3,635		—		3,635		—		—
Total	$	4,525	$	4,525	$	—	$	3,635	$	—	$	890

							Fair Value Measurements as of December 31, 2010
	Carrying Amount		Total Fair Value		Cash		Level 1		Level 2		Level 3
Measured on a recurring basis:
Assets:
Cash	$	72,422	$	72,422	$	72,422	$	—	$	—	$	—
Cash equivalents	120,042		120,042		—		120,042		—		—
Short-term—marketable securities	31,192		31,192		—		4,822		26,370		—
Non-Qualified Deferred Compensation Plan funds	2,971		2,971		—		2,971		—		—
Total	$	226,627	$	226,627	$	72,422	$	127,835	$	26,370	$	—
Liabilities:
Earnout payment liability	$	1,365	$	1,365	$	—	$	—	$	—	$	1,365
Non-Qualified Deferred Compensation Plan	2,971		2,971		—		2,971		—		—
Total	$	4,336	$	4,336	$	—	$	2,971	$	—	$	1,365

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation

Ending earnout payment liability December 31, 2009	$	1,509
Accretion	323
Change in estimate	(467		)
Ending earnout payment liability December 31, 2010	$	1,365
Accretion	206
Change in estimate	(681		)
Ending earnout payment liability December 31, 2011	$	890