3.	Cash and Available for Sale Securities

The following table summarizes the Company's cash and available-for-sale securities' amortized cost and estimated fair value by significant investment category as of December 31, 2011 and 2010 (in thousands):

	Amortized Cost and Estimated Fair Value
	December 31,
	2011		2010
Cash and cash equivalents:
Cash	$	7,205	$	9,435
Cash equivalents
Money market mutual funds		1,045		35
Certificates of deposit		3,100		2,000
Commercial paper		6,600		10,649
Total cash equivalents		10,745		12,684
Total cash and cash equivalents		17,950		22,119
Short-term investments:
Corporate bonds		2,031		-
Certificates of deposit		3,278		2,250
Commercial paper		1,500		1,000
Total short-term investments		6,809		3,250
Long-term investments:
Corporate bonds		-		1,577
Total long-term investments		-		1,577
Total cash and available-for-sale securities	$	24,759	$	26,946

Realized gains and realized losses were not significant for either of the years ended December 31, 2011 or 2010. As of December 31, 2011 and 2010, there were no significant unrealized losses on investments. The cost of all securities sold is based on the specific identification method.

The contractual maturities of cash equivalents and short-term investments at December 31, 2011 were less than one year. There were no long-term investments at December 31, 2011.

The Company typically invests in highly-rated securities, and its policy generally limits the amount of credit exposure to any one issuer. When evaluating the investments for other-than-temporary impairment, the Company reviews such factors as the length of time and extent to which fair value has been below cost basis, the financial condition of the issuer, and the Company's intent to sell, or whether it is more likely than not it will be required to sell, the investment before recovery of the investment's amortized cost basis. During the years ended December 31, 2011 and 2010, the Company did not recognize any impairment charges on outstanding investments. As of December 31, 2011, the Company does not consider any of its investments to be other-than-temporarily impaired.