Short-Term Investments

Marketable securities are classified as available-for-sale. These securities are reported at fair value with any changes in market value reported as a part of comprehensive income. Premiums (discounts) are amortized (accreted) to interest income over the life of the investment. Marketable securities are classified as short-term investments if the remaining maturity from the date of purchase is in excess of 90 days.

The Company determines the fair value amounts by using available market information. As of December 31, 2012, and December 31, 2011, the average contractual maturity was less than 12 months and the contractual maturity of any single investment did not exceed 12 months.

As of December 31, 2012, and December 31, 2011, unrealized gains and losses on available-for-sale securities are summarized as follows (in thousands):



December 31, 2012	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash, Cash Equivalents and Available-for-Sale Securities
Obligations of U.S. government agencies	$	9,013	$	1	$	(1	)	$	9,013
Obligations of U.S. corporations	6,953		—		(1		)	6,952
Obligations of Non-U.S. corporations	3,336		—		—			3,336
Money market funds	905		—		—			905
Cash	58,039		—		—			58,039
	$	78,246	$	1	$	(2	)	$	78,245
Amounts included in cash and cash equivalents	$	58,944	$	—	$	—		$	58,944
Amounts included in short-term investments	19,302		1		(2		)	19,301
	$	78,246	$	1	$	(2	)	$	78,245



December 31, 2011	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
Cash, Cash Equivalents and Available-for-Sale Securities
Obligations of U.S. government agencies	$	6,219	$	1	$	(1	)	$	6,219
Obligations of U.S. corporations	2,633		—		(3		)	2,630
Obligations of Non-U.S. corporations	1,048		—		—			1,048
Agency bonds	275		—		—			275
Money market funds	10,035		—		—			10,035
Cash	65,016		—		—			65,016
	$	85,226	$	1	$	(4	)	$	85,223
Amounts included in cash and cash equivalents	$	75,326	$	—	$	—		$	75,326
Amounts included in short-term investments	9,900		1		(4		)	9,897
	$	85,226	$	1	$	(4	)	$	85,223

As of December 31, 2012 and December 31, 2011, the Company’s cash equivalents were primarily in the form of money market funds, and the Company had no significant unrealized gains or losses on any of these investments. Cash equivalents were $0.9 million and $10.3 million as of December 31, 2012 and December 31, 2011, respectively.