Marketable Securities

9 Months Ended

Sep. 30, 2012

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

MARKETABLE SECURITIES

Our investments with original maturities of more than three months at time of purchase are considered marketable securities available for sale.

The composition of our marketable securities is as follows (in thousands):

	September 30,				December 31,
	2012				2011
	Cost		Fair Value		Cost		Fair Value
Commercial paper	$	748	$	748	$	2,395	$	2,395
Certificates of deposit	9,769		9,769		8,333		8,326
Corporate bonds/notes	10,927		10,926		7,534		7,523
Municipal bonds/notes	287		287		—		—
Agency bonds/notes	900		901		7,320		7,323
Total marketable securities	$	22,631	$	22,631	$	25,582	$	25,567

The maturities of our marketable securities available for sale as of September 30, 2012 are as follows:

	Earliest		Latest
Commercial paper	4/5/2013	to	4/5/2013
Certificates of deposit	10/14/2012	to	2/18/2014
Corporate bonds/notes	10/1/2012	to	1/15/2014
Municipal bonds/notes	9/1/2013	to	9/1/2013
Agency bonds/notes	7/1/2013	to	7/1/2013

The value and liquidity of the marketable securities we hold are affected by market conditions, as well as the ability of the issuers of such securities to make principal and interest payments when due, and the functioning of the markets in which these securities are traded. Our current investments in marketable securities are expected to be liquidated during the next twelve months.

As of September 30, 2012, we do not believe any of the underlying issuers of our marketable securities are presently at risk of default.