Investments (Tables)

3 Months Ended

Jul. 27, 2013

Investments

Schedule of investments

Investments consist of the following (in thousands):

	July 27,2013		April 30,2013
Short-term investments:
Held-to-maturity securities:
Municipal securities	$	64,474	$	73,241
Total short-term investments	$	64,474	$	73,241
Long-term investments:
Held-to-maturity securities:
Municipal securities	$	56,484	$	54,158
Available-for-sale securities:
Auction rate securities	5,444		5,687
Convertible bonds	5,667		9,071
Total long-term investments	$	67,595	$	68,916

Schedule of amortized cost, gross unrealized gains, gross unrealized losses and estimated fair value of securities held-to-maturity investments

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the held-to-maturity investments as of July 27, 2013, were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses			Fair Value
Municipal securities	$	120,958	$	75	$	(32	)	$	121,001
Total held-to-maturity investments	$	120,958	$	75	$	(32	)	$	121,001

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the held-to-maturity investments as of April 30, 2013, were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses			Fair Value
Municipal securities	$	127,399	$	49	$	(23	)	$	127,425
Total held-to-maturity investments	$	127,399	$	49	$	(23	)	$	127,425

Held-to-maturity securities

Investments

Schedule of amortized cost and fair value by contractual maturity

The amortized cost and fair value of the held-to-maturity securities by contractual maturity at July 27, 2013, were as follows (in thousands):

	Cost		Fair Value
Due within one year	$	64,474	$	64,503
Due after one year through three years	56,484		56,498
Total	$	120,958	$	121,001

Available-for-sale securities | Auction rate securities

Investments

Schedule of amortized cost, gross unrealized gains, gross unrealized losses and estimated fair value of available-for-sale investments

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the available-for-sale investments as of July 27, 2013, were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses			Fair Value
Auction rate securities	$	6,575	$	—	$	(1,131	)	$	5,444
Total available-for-sale investments	$	6,575	$	—	$	(1,131	)	$	5,444

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the available-for-sale investments as of April 30, 2013, were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses			Fair Value
Auction rate securities	$	6,750	$	—	$	(1,063	)	$	5,687
Total available-for-sale investments	$	6,750	$	—	$	(1,063	)	$	5,687

Schedule of amortized cost and fair value by contractual maturity

The amortized cost and fair value of the auction rate securities by contractual maturity at July 27, 2013, were as follows (in thousands):

	Cost		Fair Value
Due after five through 10 years	$	1,350	$	1,242
Due after 10 years	5,225		4,202
Total	$	6,575	$	5,444

Available-for-sale securities | Convertible bonds

Investments

Schedule of amortized cost, gross unrealized gains, gross unrealized losses and estimated fair value of available-for-sale investments

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the available-for-sale convertible bonds as of July 27, 2013, were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses			Fair Value
Convertible bonds	$	3,037	$	2,781	$	(151	)	$	5,667
Total available-for-sale investments	$	3,037	$	2,781	$	(151	)	$	5,667

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the available-for-sale convertible bonds as of April 30, 2013, were as follows (in thousands):

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses			Fair Value
Convertible bonds	$	3,037	$	6,173	$	(139	)	$	9,071
Total available-for-sale investments	$	3,037	$	6,173	$	(139	)	$	9,071

Schedule of amortized cost and fair value by contractual maturity

The amortized cost and fair value of the convertible bonds by contractual maturity at July 27, 2013, were as follows (in thousands):

	Cost		Fair Value
Due within five years	$	3,037	$	5,667
Total	$	3,037	$	5,667