Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2014

Fair Value Disclosures [Abstract]

Schedule of Fair Value Hierarchy of Financial Assets Carried at Fair Value and Measured on Recurring Basis

The fair value hierarchy of the Company’s financial assets carried at fair value and measured on a recurring basis was as follows (in thousands):

			Fair value measurements at the reporting date using
	June 30, 2014		Quoted prices in active markets using identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Cash equivalents:
Money market and other funds	$	23,128	$	—	$	23,128	$	—
Commercial paper	7,299		—		7,299		—
Time deposits	598		—		598		—
Taxable municipal bonds	10,137		—		10,137		—
Total cash equivalents	41,162		—		41,162		—
Available-for-sale investments:
Debt securities:
U.S. government securities	51,791		—		51,791		—
Commercial paper	22,094		—		22,094		—
Time deposits	22,669		—		22,669		—
Corporate bonds	1,538		—		1,538		—
Taxable municipal bonds	104,195		—		104,195		—
Total debt securities	202,287		—		202,287		—
Equity securities	6,569		6,569		—		—
Total available-for-sale investments	208,856		6,569		202,287		—
Total assets at fair value	$	250,018	$	6,569	$	243,449	$	—
			Fair value measurements at the reporting date using
	December 31, 2013		Quoted prices in active markets using identical assets (Level 1)		Significant other observable inputs (Level 2)		Significant unobservable inputs (Level 3)
Cash equivalents:
U.S. government securities	$	6,400	$	—	$	6,400	$	—
Money market and other funds	9,391		—		9,391		—
Commercial paper	17,999		—		17,999		—
Time deposits	499		—		499		—
Taxable municipal bonds	21,215		—		21,215		—
Total cash equivalents	55,504		—		55,504		—
Available-for-sale investments:
U.S. government securities	58,114		—		58,114		—
Commercial paper	14,496		—		14,496		—
Time deposits	9,880		—		9,880		—
Taxable municipal bonds	120,990		—		120,990		—
Total available-for-sale investments	203,480		—		203,480		—
Total assets at fair value	$	258,984	$	—	$	258,984	$	—

Investments Classified as Available-for-Sale

The cost and fair value of available-for-sale investments were as follows (in thousands):

		Amortized cost		Gross unrealized gains		Gross unrealized losses			Fair value
Available-for-sale investments as of	June 30, 2014
Debt securities		$	202,266	$	30	$	(9	)	$	202,287
Equity securities		4,493		2,076		—			6,569
Total		$	206,759	$	2,106	$	(9	)	$	208,856
Available-for-sale investments as of	December 31, 2013	$	203,479	$	24	$	(23	)	$	203,480