Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Assets And Liabilities Measured At Fair Value

The following table presents information about the Company's assets and liabilities measured at fair value:

			Fair Value Measurements at September 30, 2016
	Total		Level 1		Level 2		Level 3
Assets
Cash equivalents	$	367,005	$	367,005	$	—	$	—
Short-term investments	126,860		126,860		—		—
Interest rate swap	164		—		164		—
Auction rate securities	1,142		—		—		1,142
Total assets	$	495,171	$	493,865	$	164	$	1,142
Liabilities
Long-term notes	$	41,620	$	—	$	41,620	$	—
Contingent purchase consideration	21		—		—		21
Total liabilities	$	41,641	$	—	$	41,620	$	21
			Fair Value Measurements at December 31, 2015
	Total		Level 1		Level 2		Level 3
Assets
Cash equivalents	$	214,232	$	214,232	$	—	$	—
Short-term investments	106,375		106,375		—		—
Auction rate securities	1,136		—		—		1,136
Total assets	$	321,743	$	320,607	$	—	$	1,136
Liabilities
Long-term notes	$	19,667	$	19,667	$	—	$	—
Contingent purchase consideration	20		—		—		20
Total liabilities	$	19,687	$	19,667	$	—	$	20

Fair Value Of Auction Rate Securities

	Three Months Ended September 30,					Nine Months Ended September 30,
	2016		2015			2016		2015
Auction Rate Securities
Balance, beginning of period	$	1,140	$	1,132		$	1,136	$	1,128
Change in fair value and accretion	2		2			6		6
Balance, end of period	$	1,142	$	1,134		$	1,142	$	1,134
Contingent Purchase Consideration
Balance, beginning of period	$	20	$	80		$	20	$	98
Period transactions	—		(7		)	—		(7		)
Change in fair value and currency fluctuations	1		(4		)	1		(22		)
Balance, end of period	$	21	$	69		$	21	$	69