Cash Equivalents and Marketable Securities

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

The total cash and cash equivalents balance of $23,163,000 as of March 31, 2014 was comprised of money market funds of $14,592,000, and $8,571,000 held as cash, primarily with major financial institutions in North America. At March 31, 2014, the Company had no marketable securities in an unrealized loss position.

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

The total cash and cash equivalents balance of $22,130,000 as of December 31, 2013, was comprised of money market funds of $16,089,000 and $6,041,000 held as cash, primarily with major financial institutions in North America. At December 31, 2013, the Company had no marketable securities in an unrealized loss position.