Cash Equivalents and Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2014

Cash Equivalents and Marketable Securities [Abstract]

Schedule of cash equivalents and marketable securities

At December 31, 2013, cash equivalents and marketable securities consisted of the following (in thousands):

	December 31, 2013
	Adjusted Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value		Average Contractual Maturities
									(in days)
Money market funds	$	16,089	$	—	$	—	$	16,089	n/a
Corporate bonds	1,002		3		—		1,005		140
U.S. Treasury obligations	2,000		—		—		2,000		59
Common shares of CO2 Solutions	563		232		—		795		n/a
Total	$	19,654	$	235	$	—	$	19,889

At March 31, 2014, cash equivalents and marketable securities consisted of the following (in thousands):

	March 31, 2014
	Adjusted Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value		Average Contractual Maturities
									(in days)
Money market funds	$	14,592	$	—	$	—	$	14,592	n/a
Corporate bonds	1,001		1		—		1,002		50
Common shares of CO2 Solutions	563		883		—		1,446		n/a
Total	$	16,156	$	884	$	—	$	17,040