Investments in Marketable Securities and Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2013

Investments in Marketable Securities and Fair Value Measurements [Abstract]

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

	September 30, 2013									December 31, 2012
			Gross		Gross							Gross		Gross
	Amortized		Unrealized		Unrealized			Fair		Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		(Losses)			Value		Cost		Gains		(Losses)			Value
Classified as:
Cash	$	24,114	$	—	$	—		$	24,114	$	26,250	$	—	$	—		$	26,250
Cash equivalents:
Money market fund		3,609		—		—			3,609		4,384		—		—			4,384

Total cash and cash equivalents		27,723		—		—			27,723		30,634		—		—			30,634

Investments (Available-for-sale):
Certificates of deposit		6,320		5		(9	)		6,316		6,638		9		(2	)		6,645
Corporate bonds		14,402		6		(25	)		14,383		12,872		7		(63	)		12,816
Total investments		20,722		11		(34	)		20,699		19,510		16		(65	)		19,461
Total cash, cash equivalents and investments	$	48,445	$	11	$	(34	)	$	48,422	$	50,144	$	16	$	(65	)	$	50,095
Contractual maturities on investments:
Due within 1 year	$	8,405						$	8,412	$	10,288						$	10,270
Due after 1 through 5 years		12,317							12,287		9,222							9,191
	$	20,722						$	20,699	$	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 September 30, 2013 (in thousands):

	In Loss Position < 12 months					In Loss Position > 12 months				Total In Loss Position
			Gross					Gross				Gross
	Fair		Unrealized			Fair		Unrealized		Fair		Unrealized
	Value		(Losses)			Value		(Losses)		Value		(Losses)
Investments:
Certificates of deposit	$	3,671	$	(9	)	$	—	$	—	$	3,671	$	(9	)
Corporate bonds		11,738		(25	)		—		—		11,738		(25	)
Total in loss position	$	15,409	$	(34	)	$	—	$	—	$	15,409	$	(34	)

	In Loss Position < 12 Months					In Loss Position > 12 Months					Total In Loss Position
	Fair Value		Gross Unrealized (Losses)			Fair Value		Gross Unrealized (Losses)			Fair Value		Gross Unrealized (Losses)
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 September 30, 2013 (in thousands):

	Balance as of September 30, 2013		Quoted Prices in Active Markets of Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)
Assets:
Cash equivalents and investments:
Money market fund	$	3,609	$	3,609	$	—
Certificates of deposit		6,316		—		6,316
Corporate bonds		14,383		—		14,383
Total	$	24,308	$	3,609	$	20,699
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 of December 31, 2012		Quoted Prices in Active Markets of Identical Assets (Level 1)		Significant Other Observable Inputs (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	$	—	$	—	$	—