Investments and Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2013

Investments and Fair Value Measurements [Abstract]

Cash, cash equivalents and investments

Our cash, cash equivalents and investments are classified as follows (in thousands):

	March 31, 2013									December 31, 2012
			Gross		Gross							Gross		Gross
	Amortized		Unrealized		Unrealized			Fair		Amortized		Unrealized		Unrealized			Fair
	Cost		Gain		(Loss)			Value		Cost		Gain		(Loss)			Value
Classified as:
Cash	$	25,789	$	—	$	—		$	25,789	$	26,250	$	—	$	—		$	26,250
Cash equivalents:
Money market fund		3		—		—			3		4,384		—		—			4,384
Total cash equivalents		3		—		—			3		4,384		—		—			4,384
Total cash and cash equivalents		25,792		—		—			25,792		30,634		—		—			30,634
Investments (available for sale):
Certificates of deposit		6,998		8		(7	)		6,999		6,638		9		(2	)		6,645
Corporate bonds		16,646		4		(71	)		16,579		12,872		7		(63	)		12,816
Total investments		23,644		12		(78	)		23,578		19,510		16		(65	)		19,461
Total cash, cash equivalents and investments	$	49,436	$	12	$	(78	)	$	49,370	$	50,144	$	16	$	(65	)	$	50,095
Contractual maturities on investments:
Due within 1 year	$	6,536						$	6,540	$	10,288						$	10,270
Due after 1 through 5 years		17,108							17,038		9,222							9,191
	$	23,644						$	23,578	$	19,510						$	19,461

Fair value and gross unrealized losses related to available-for-sale securities

The following table summarizes the fair value and gross unrealized losses related to available-for-sale securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of March 31, 2013 (in thousands):

	In Loss Position < 12 Months					In Loss Position > 12 Months				Total In Loss Position
	Fair Value		Gross Unrealized (Loss)			Fair Value		Gross Unrealized (Loss)		Fair Value		Gross Unrealized (Loss)
Investments:
Certificates of deposit	$	2,953	$	(7	)	$	—	$	—	$	2,953	$	(7	)
Corporate bonds		12,788		(71	)		—		—		12,788		(71	)
Total in loss position	$	15,741	$	(78	)	$	—	$	—	$	15,741	$	(78	)

The following table summarizes the fair value and gross unrealized losses related to available-for-sale securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of December 31, 2012 (in thousands):

	In Loss Position < 12 Months					In Loss Position > 12 Months					Total In Loss Position
	Fair Value		Gross Unrealized (Loss)			Fair Value		Gross Unrealized (Loss)			Fair Value		Gross Unrealized (Loss)
Investments:
Certificates of deposit	$	1,877	$	(1	)	$	199	$	(1	)	$	2,076	$	(2	)
Corporate bonds		6,446		(40	)		1,502		(23	)		7,948		(63	)
Total in loss position	$	8,323	$	(41	)	$	1,701	$	(24	)	$	10,024	$	(65	)

Summary of financial assets and liabilities measured at fair value on a recurring basis

The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis as of March 31, 2013 (in thousands):

	Balance as ofMarch 31, 2013		Quoted Prices inActive Markets ofIdentical Assets(Level 1)		Significant OtherObservableInputs(Level 2)
Assets:
Cash equivalents and investments:
Money market fund	$	3	$	3	$	—
Certificates of deposit		6,999		—		6,999
Corporate bonds		16,579		—		16,579
Total	$	23,581	$	3	$	23,578
Liabilities	$	—	$	—	$	—

The following table summarizes our financial assets and liabilities measured at fair value on a recurring basis as of December 31, 2012 (in thousands):

	Balance as ofDecember 31, 2012		Quoted Prices inActive Markets ofIdentical Assets(Level 1)		Significant OtherObservableInputs(Level 2)
Assets:
Cash equivalents and investments:
Money market fund	$	4,384	$	4,384	$	—
Certificates of deposit		6,645		—		6,645
Corporate bonds		12,816		—		12,816
Total	$	23,845	$	4,384	$	19,461
Liabilities	$	—	$	—	$	—