Investments in Marketable Securities

6 Months Ended

Jun. 30, 2012

Investments in Marketable Securities [Abstract]

Investments in Marketable Securities

7. Investments in Marketable Securities

The cost, gross unrealized holding gains, gross unrealized holding losses and fair value of available-for-sale investments by types and classes of security at June 30, 2012 and December 31, 2011 consisted of the following (in thousands):

At June 30, 2012	Amortized     Cost Basis		Other-than-     temporary Impairments		Gross Unrealized     Holding Gains		Gross Unrealized     Holding Losses		Fair Value
Available-for-sale:
Debt instruments – Municipal debt obligations	$	2,772	$	—	$	—	$	—	$	2,772
Certificates of deposit		1,000		—		—		—		1,000
	$	3,772	$	—	$	—	$	—	$	3,772

At December 31, 2011	Amortized     Cost Basis		Other-than-     temporary Impairments		Gross Unrealized     Holding Gains		Gross Unrealized     Holding Losses			Fair Value
Available-for-sale:
Debt instruments – Corporate debt obligations	$	37,392	$	—	$	3	$	(1	)	$	37,394
Debt instruments – Municipal debt obligations		6,224		—		—		—			6,224
Certificates of deposit		1,000		—		—		—			1,000
	$	44,616	$	—	$	3	$	(1	)	$	44,618

Investments by contractual maturity are as follows (in thousands):

	June 30, 2012				December 31, 2011
	Cost		Fair Value		Cost		Fair Value
Due or callable in one year or less	$	3,772	$	3,772	$	44,616	$	44,618
Due after one year	$	—	$	—	$	—	$	—

No gains or losses were realized on the sale of marketable securities using the specific identification method during the three and six months ended June 30, 2012 and 2011, respectively. Further, as of June 30, 2012 the Company held no investments in an unrealized loss position. As of December 31, 2011, the Company held two investments in an unrealized loss position, each of which had been in such a position for less than twelve months. During the six month ended June 30, 2012, these positions matured and no gains or losses were recognized.