7.	Cash, Cash Equivalents and Marketable Securities

At March 31, 2013 and December 31, 2012, the Company’s investments included money market funds as well as short-term and long-term marketable securities. These marketable securities are classified as available-for-sale. Marketable securities are investments with original maturities of greater than 90 days. Long-term marketable securities are securities with maturities of greater than one year. The average remaining contractual maturity of marketable securities at March 31, 2013 is approximately 9.21 months.

Management reviewed the Company’s investments as of March 31, 2013 and December 31, 2012 and concluded that there are no securities with other than temporary impairments in the investment portfolio. The Company does not intend to sell any investments in an unrealized loss position and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases.

Investments in debt securities consisted of the following at March 31, 2013:


	March 31, 2013
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
Marketable securities:
U.S. Government and agency securities	$	2,084,913	$	208	$	—		$	2,085,121
Corporate and other debt securities		17,242,580		11,159		(1,736	)		17,252,003

		19,327,493		11,367		(1,736	)		19,337,124
Long-term marketable securities:
U.S. Government and agency securities		5,324,930		2,457		(209	)		5,327,178
Corporate and other debt securities		820,643		306		(38	)		820,911

		6,145,573		2,763		(247	)		6,148,089

Total	$	25,473,066	$	14,130	$	(1,983	)	$	25,485,213

At March 31, 2013, the Company’s investments included twelve debt securities in unrealized loss positions with a total unrealized loss of approximately $2,000 and a total fair market value of approximately $9,305,000. All investments with gross unrealized losses have been in unrealized loss positions for less than 12 months. The unrealized losses were caused primarily by current economic and market conditions. There was no change in the credit risk of the securities. There were no realized gains or losses on the investments for the three months ended March 31, 2013 or the year ended December 31, 2012.

Investments in debt securities consisted of the following at December 31, 2012:


	December 31, 2012
	Amortized Cost		Gross Unrealized Gain		Gross Unrealized Loss			Fair Value
Marketable securities:
U.S. Government and agency securities	$	2,000,897	$	353	$	(7	)	$	2,001,243
Corporate and other debt securities		8,835,098		8,854		—			8,843,952

		10,835,995		9,207		(7	)		10,845,195
Long-term marketable securities:
U.S. Government and agency securities		5,198,264		2,747		—			5,201,011
Corporate and other debt securities		4,711,679		3,525		(1,360	)		4,713,844

		9,909,943		6,272		(1,360	)		9,914,855

Total	$	20,745,938	$	15,479	$	(1,367	)	$	20,760,050

The contractual maturities of debt securities at March 31, 2013 were as follows:


	Amortized Cost		Fair Value
Due in 1 year or less	$	19,327,496	$	19,337,124
Due in 1 to 2 years		6,145,573		6,148,089

	$	25,473,069	$	25,485,213