Fair Value Measurements (Tables)

12 Months Ended

Mar. 31, 2011

Mar. 31, 2010

Notes to Financial Statements [Abstract]

Assets measured at fair value on a recurring basis (in details)

Assets measured at fair value on a recurring basis at March 31, 2011 are as follows (amounts in thousands):

	Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Balance
Assets
Money market fund deposits	$	464,669	$	---	$	---	$	464,669
Marketable equity securities		26,861		---		---		26,861
Corporate bonds & debt		---		519,526		3,500		523,026
Government agency bonds		---		430,591		---		430,591
Deposit accounts		---		239,254		---		239,254
Municipal bonds		---		11,457		---		11,457
Auction Rate Securities		---		---		12,475		12,475
Total assets measured at fair value	$	491,530	$	1,200,828	$	15,975	$	1,708,333

Assets measured at fair value on a recurring basis at March 31, 2010 are as follows (amounts in thousands):

	Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Balance
Assets
Money market fund deposits	$	206,376	$	---	$	---	$	206,376
Deposit accounts		---		285,754		---		285,754
Government agency bonds		---		389,394		---		389,394
Municipal bonds		---		157,705		---		157,705
ARS		---		---		37,237		37,237
Put option on ARS		---		---		1,814		1,814
Corporate bonds		---		394,856		---		394,856
Marketable equity securities		58,402		---		---		58,402
Total assets measured at fair value	$	264,778	$	1,227,709	$	39,051	$	1,531,538

Reconciliation for all assets measured at fair value on a recurring basis

The following tables present a reconciliation for all assets measured at fair value on a recurring basis, excluding accrued interest components, using significant unobservable inputs (Level 3) for the years ended March 31, 2011 and March 31, 2010 (amounts in thousands):

Year Ended March 31, 2011	Auction Rate Securities			Put Option on Auction Rate Securities			Corporate Debt		Total Gains (Losses)
Balance at March 31, 2010	$	37,237		$	1,814		$	---	$	---
Total gains or losses (realized and unrealized):
Included in earnings		138			(1,814	)		---		(1,676	)
Purchases, sales, issuances, and settlements, net		(24,900	)		---			3,500		---
Balance at March 31, 2011	$	12,475		$	---		$	3,500	$	(1,676	)

Year Ended March 31, 2010	Auction Rate Securities			Put Option on Auction Rate Securities			Corporate Debt		Total Gains (Losses)
Balance at March 31, 2009	$	46,800		$	4,026		$	---	$	---
Total gains or losses (realized and unrealized):
Included in earnings		(2,538	)		(2,212	)		---		(4,750	)
Purchases, sales, issuances, and settlements, net		(7,025	)		---			---		---
Balance at March 31, 2010	$	37,237		$	1,814		$	---	$	(4,750	)

Assets measured at fair value on a recurring basis (as presented in consolidated balance sheets)

Assets measured at fair value on a recurring basis are presented/classified on the consolidated balance sheets at March 31, 2011 as follows (amounts in thousands):

	Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Balance
Assets
Cash and cash equivalents	$	464,669	$	239,254	$	---	$	703,923
Short-term investments		16,553		523,019		---		539,572
Long-term investments		10,308		438,555		15,975		464,838
Total assets measured at fair value	$	491,530	$	1,200,828	$	15,975	$	1,708,333

Assets measured at fair value on a recurring basis are presented/classified in the consolidated balance sheets at March 31, 2010 as follows (amounts in thousands):

	Quoted Prices in Active Markets for Identical Instruments (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total Balance
Assets
Cash and cash equivalents	$	206,376	$	285,754	$	---	$	492,130
Short-term investments		58,402		638,891		24,900		722,193
Long-term investments		---		303,064		14,151		317,215
Total assets measured at fair value	$	264,778	$	1,227,709	$	39,051	$	1,531,538