Investments (Tables)

3 Months Ended

Jul. 28, 2018

Investments

Schedule of investments

Investments consist of the following (in thousands):

	July 28,		April 30,
	2018		2018
Short-term investments:
Held-to-maturity securities:
Municipal securities	$	14,964	$	35,344
U.S. government securities		33,514		31,620
Corporate bonds		66,825		46,685
Certificates of deposit		3,000		—
Total held-to-maturity and short-term investments	$	118,303	$	113,649
Long-term investments:
Held-to-maturity securities:
Municipal securities	$	2,031	$	2,046
U.S. government securities		28,809		27,356
Corporate bonds		5,872		9,112
Total held-to-maturity investments		36,712		38,514
Available-for-sale securities:
Auction rate securities		—		2,142
Total available-for-sale investments		—		2,142
Total long-term investments	$	36,712	$	40,656

Held to maturity securities

Investments

Schedule of amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of 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 28, 2018 were as follows (in thousands):

	July 28, 2018
			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
Municipal securities	$	16,995	$	8	$	(3)	$	17,000
U.S. government securities		62,323		—		(307)		62,016
Corporate bonds		72,697		1		(53)		72,645
Certificates of deposit		3,000		—		—		3,000
Total held-to-maturity investments	$	155,015	$	9	$	(363)	$	154,661

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the held-to-maturity investments as of April 30, 2018 were as follows (in thousands):

	April 30, 2018
			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
Municipal securities	$	37,390	$	9	$	(36)	$	37,363
U.S. government securities		58,976		—		(367)		58,609
Corporate bonds		55,797		2		(71)		55,728
Certificates of deposit		—		—		—		—
Total held-to-maturity investments	$	152,163	$	11	$	(474)	$	151,700

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 28, 2018 were as follows (in thousands):

	Cost		Fair Value
Due within one year	$	118,303	$	118,120
Due after one year through five years		36,712		36,541
Total	$	155,015	$	154,661

Available-for-sale securities | Auction rate securities

Investments

Schedule of amortized cost and fair value by contractual maturity

			Gross		Gross
	Amortized		Unrealized		Unrealized
	Cost		Gains		Losses		Fair Value
Auction rate securities	$	2,250	$	—	$	(108)	$	2,142
Total available-for-sale investments	$	2,250	$	—	$	(108)	$	2,142