Note 5 - Fair Value (Tables)

12 Months Ended

Mar. 29, 2015

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

	March 29, 2015
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	6	$	—	$	—	$	6
Common shares of CounterPath		—		48		—		48
Total investment assets	$	6	$	48	$	—	$	54

	March 30, 2014
	Level 1		Level 2		Level 3		Total
Assets:
Money market funds	$	4,636	$	—	$	—	$	4,636
U.S. government and agency securities		9,378		13,134		—		22,512
State and local government securities		—		2,772		—		2,772
Corporate bonds and securities		5		71,248		—		71,253
Asset-backed securities		—		27,635		—		27,635
Mortgage-backed securities		—		28,248		—		28,248
Total investment assets	$	14,019	$	143,037	$	—	$	157,056
Liabilities:
Acquisition-related contingent consideration – Altior	$	—	$	—	$	2,973	$	2,973
Acquisition-related contingent consideration – Cadeka	$	—	$	—	$	1,370	$	1,370
Total liabilities	$	—	$	—	$	4,343	$	4,343

Schedule of Business Acquisitions by Acquisition, Contingent Consideration [Table Text Block]

	Amount
As of April 1, 2012	$	—
Estimated contingent consideration liability		10,138
As of March 31, 2013		10.138
Fair value adjustment		(7,165	)
As of March 30, 2014		2,973
Fair value adjustment		(2,973	)
As of March 29, 2015	$	—

	Amount
As of March 31, 2013	$	—
Estimated contingent consideration liability		4,660
Fair value adjustment		(3,290	)
As of March 30, 2014		1,370
Fair value adjustment		(1,370	)
As of March 29, 2015	$	—

Marketable Securities [Table Text Block]

	March 29, 2015		March 30, 2014
Cash and cash equivalents
Cash in financial institutions	$	55,227	$	9,978
Money market funds		6		4,636
Total cash and cash equivalents	$	55,233	$	14,614
Short-term marketable securities
U.S. government and agency securities	$	—	$	22,512
State and local government securities		—		2,772
Corporate bonds and securities		—		71,253
Asset-backed securities		—		27,635
Mortgage-backed securities		—		28,248
Total short-term marketable securities	$	—	$	152,420

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

	Fiscal Years Ended
	March 29, 2015			March 30, 2014			March 31, 2013
Gross realized gains	$	264		$	748		$	871
Gross realized losses		(238	)		(547	)		(953	)
Net realized gains (losses)	$	26		$	201		$	(82	)

Available-for-sale Securities [Table Text Block]

	March 30, 2014
	Amortized Cost		Unrealized Gross Gains(1)		Unrealized Gross Losses(1)			Fair Value
Money market funds	$	4,636	$	—	$	—		$	4,636
U.S. government and agency securities		22,550		1		(39	)		22,512
State and local government securities		2,762		10		—			2,772
Corporate bonds and securities		71,309		32		(88	)		71,253
Asset-backed securities		27,661		22		(48	)		27,635
Mortgage-backed securities		28,362		24		(138	)		28,248
Total investments	$	157,280	$	89	$	(313	)	$	157,056

Investments Classified by Contractual Maturity Date [Table Text Block]

	March 30, 2014
	Amortized Cost		Fair Value
Less than 1 year	$	49,539	$	49,504
Due in 1 to 5 years		107,741		107,552
Total	$	157,280	$	157,056

Schedule of Unrealized Loss on Investments [Table Text Block]

	March 30, 2014
	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	$	18,245	$	(39	)	$	—	$	—		$	18,245	$	(39	)
Corporate bonds and securities		48,379		(87	)		596		(1	)		48,975		(88	)
Asset-backed securities		7,118		(12	)		5,478		(36	)		12,596		(48	)
Mortgage-backed securities		19,682		(120	)		983		(18	)		20,665		(138	)
Total	$	93,424	$	(258	)	$	7,057	$	(55	)	$	100,481	$	(313	)