Note 4 - Fair Value (Tables)

9 Months Ended

Dec. 29, 2013

Fair Value Disclosures [Abstract]

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

	December 29, 2013
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	13,961	$	—	$	—	$	13,961
U.S. government and agency securities		11,537		21,254		—		32,791
State and local government securities		—		2,798		—		2,798
Corporate bonds and securities		4		72,721		—		72,725
Asset-backed securities		—		30,354		—		30,354
Mortgage-backed securities		—		16,034		—		16,034
Total investment assets	$	25,502	$	143,161	$	—	$	168,663
Liabilities:
Acquisition-related contingent consideration – Altior	$	—	$	—	$	7,741	$	7,741
Acquisition-related contingent consideration – Cadeka	$	—	$	—	$	4,620	$	4,620
Total liabilities	$	—	$	—	$	12,361	$	12,361

	March 31, 2013
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	5,042	$	—	$	—	$	5,042
U.S. government and agency securities		22,460		19,261		—		41,721
State and local government securities		—		2,935		—		2,935
Corporate bonds and securities		274		91,955		—		92,229
Asset-backed securities		—		30,966		—		30,966
Mortgage-backed securities		—		22,736		—		22,736
Total investment assets	$	27,776	$	167,853	$	—	$	195,629
Liabilities:
Acquisition-related contingent consideration – Altior	$	—	$	—	$	10,138	$	10,138

Fair Value Inputs, Assets, Quantitative Information [Table Text Block]

	Fair Value (in thousands)		Valuation Technique	Significant Unobservable Input
As of December 29, 2013
Acquisition-related contingent consideration – Altior	$	7,741	Combination of income and marketable approach	Revenue and Probability of Achievement
Acquisition-related contingent consideration – Cadeka	$	4,620	Combination of income and marketable approach	Revenue and Probability of Achievement

Schedule of Change in Fair Value of Purchase Consideration Liability [Table Text Block]

	December 29, 2013
As of March 31, 2013	$	10,138
Less: Adjustment to purchase consideration		(2,397	)
As of December 29, 2013	$	7,741

	December 29, 2013
As of March 31, 2013	$	—
Purchase contingent consideration		4,660
Less: Adjustment to purchase consideration		(40	)
As of December 29, 2013	$	4,620

Marketable Securities [Table Text Block]

	December29, 2013		March 31, 2013
Cash and cash equivalents
Cash at financial institutions	$	7,109	$	9,676
Cash equivalents
Money market funds		13,961		5,042
Total cash and cash equivalents	$	21,070	$	14,718
Available-for-sale securities
U.S. government and agency securities	$	32,791	$	41,721
State and local government securities		2,798		2,935
Corporate bonds and securities		72,725		92,229
Asset-backed securities		30,354		30,966
Mortgage-backed securities		16,034		22,736
Total short-term marketable securities	$	154,702	$	190,587

Realized Gain (Loss) on Investments [Table Text Block]

	Three Months Ended						Nine Months Ended
	December 29, 2013			December 30, 2012			December 29, 2013			December 30, 2012
Gross realized gains	$	136		$	233		$	518		$	617
Gross realized losses		(69	)		(229	)		(477	)		(766	)
Net realized income (losses)	$	67		$	4		$	41		$	(149	)

Available-for-sale Securities [Table Text Block]

	December 29, 2013
	Amortized Cost		Unrealized Gross Gains (1)		Unrealized Gross Losses (1)			Fair Value
Money market funds	$	13,961	$	—	$	—		$	13,961
U.S. government and agency securities		32,840		1		(50	)		32,791
State and local government securities		2,797		5		(4	)		2,798
Corporate bonds and securities		72,730		60		(65	)		72,725
Asset-backed securities		30,396		14		(56	)		30,354
Mortgage-backed securities		16,064		19		(49	)		16,034
Total investments	$	168,788	$	99	$	(224	)	$	168,663

	March 31, 2013
	Amortized Cost		Unrealized Gross Gains (1)		Unrealized Gross Losses (1)			Fair Value
Money market funds	$	5,042	$	—	$	—		$	5,042
U.S. government and agency securities		41,694		27		—			41,721
State and local government securities		2,927		10		(2	)		2,935
Corporate bonds and securities		92,059		215		(45	)		92,229
Asset-backed securities		30,932		61		(27	)		30,966
Mortgage-backed securities		22,646		194		(104	)		22,736
Total investments	$	195,300	$	507	$	(178	)	$	195,629

Investments Classified by Contractual Maturity Date [Table Text Block]

	December 29, 2013				March 31, 2013
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Less than 1 year	$	61,616	$	61,615	$	61,011	$	61,029
Due in 1 to 5 years		107,172		107,048		134,289		134,600
Total	$	168,788	$	168,663	$	195,300	$	195,629

Schedule of Unrealized Loss on Investments [Table Text Block]

	December 29, 2013
	Less than 12 months					12 months or greater					Total
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
U.S. government and agency securities	$	28,772	$	(50	)	$	—	$	—		$	28,772	$	(50	)
State and local government securities		1,516		(4	)		—		—			1,516		(4	)
Corporate bonds and securities		35,179		(65	)		—		—			35,179		(65	)
Asset-backed securities		15,301		(25	)		3,467		(31	)		18,768		(56	)
Mortgage-backed securities		8,249		(22	)		2,174		(27	)		10,423		(49	)
Total	$	89,017	$	(166	)	$	5,641	$	(58	)	$	94,658	$	(224	)

	March 31, 2013
	Less than 12 months					12 months or greater					Total
	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
State and local government securities	$	—	$	—		$	404	$	(2	)	$	404	$	(2	)
Corporate bonds and securities		29,609		(42	)		497		(3	)		30,106		(45	)
Asset-backed securities		10,008		(17	)		1,241		(10	)		11,249		(27	)
Mortgage-backed securities		2,911		(39	)		3,263		(65	)		6,174		(104	)
Total	$	42,528	$	(98	)	$	5,405	$	(80	)	$	47,933	$	(178	)