Marketable Securities

3 Months Ended

Jun. 30, 2012

Marketable Securities [Abstract]

Marketable Securities

3.Marketable Securities

The Company’s investments that have original maturities greater than 90 days have been classified as available-for-sale securities in accordance with U.S. GAAP.Marketable securities are categorized on the consolidated condensed balance sheet as short- and long-term marketable securities, as appropriate.

The following table is a summary of available-for-sale securities at June 30, 2012 (in thousands):

							Estimated
			Gross		Gross		Fair Value
	Amortized		Unrealized		Unrealized		(Net Carrying
	Cost		Gains		Losses		Amount)
Corporate debt securities	$	32,554	$	21	$	(12)	$	32,563
U.S. Treasury securities		16,762		2		(2)		16,762
Agency discount notes		17,028		4		-		17,032
Commercial paper		16,006		4		(8)		16,002
Total securities	$	82,350	$	31	$	(22)	$	82,359

The Company’s specifically identified gross unrealized losses of $22 thousand relates to 16 different securities with total amortized cost of approximately $31.1 million at June 30, 2012. Because the Company does not intend to sell the investments at a loss and the Company will not be required to sell the investments before recovery of its amortized cost basis, it did not consider the investment in these securities to be other-than-temporarily impaired at June 30, 2012. Further, the securities with gross unrealized losses had been in a continuous unrealized loss position for less than 12 months as of June 30, 2012.All of the Company’s available-for-sale investments have contractual maturities of less than one year at June 30, 2012.

The following table is a summary of available-for-sale securities at March 31, 2012 (in thousands):

							Estimated
			Gross		Gross		Fair Value
	Amortized		Unrealized		Unrealized		(Net Carrying
	Cost		Gains		Losses		Amount)
Corporate debt securities	$	48,011	$	33	$	(19)	$	48,025
U.S. Treasury securities		30,264		1		(4)		30,261
Agency discount notes		16,789		8		(1)		16,796
Commercial paper		23,719		5		(15)		23,709
Total securities	$	118,783	$	47	$	(39)	$	118,791

The Company’s specifically identified gross unrealized losses of $39 thousand relates to 37 different securities with total amortized cost of approximately $72.6 million at March 31, 2012.Because the Company does not intend to sell the investments at a loss and the Company will not be required to sell the investments before recovery of its amortized cost basis, it did not consider the investment in these securities to be other-than-temporarily impaired at March 31, 2012. Further, the securities with gross unrealized losses had been in a continuous unrealized loss position for less than 12 months as of March 31, 2012.