Marketable Securities

12 Months Ended

Jan. 31, 2020

Investments Debt And Equity Securities [Abstract]

4. Marketable Securities

During all periods shown, marketable securities are classified as available-for-sale. The amortized cost, gross unrealized gains (losses) and fair values of available-for-sale securities by major security type and class of security as of January 31, 2020 and 2019 are as follows:

	Amortized Cost		Unrealized Gains		Unrealized (Losses)			Fair Value
As of January 31, 2020
Short-term Investments:
Corporate bonds	$	166,790	$	318	$	(26	)	$	167,082
Municipal and pre-refunded municipal bonds		38,617		20		(11	)		38,626
Federal government agencies		1,152		3		—			1,155
Certificate of deposit		2,593		—		—			2,593
Commercial paper		1,997		—		—			1,997
		211,149		341		(37	)		211,453
Long-term Investments:
Corporate bonds		47,352		205		(40	)		47,517
Municipal and pre-refunded municipal bonds		30,340		35		(17	)		30,358
Mutual funds, held in rabbi trust		8,448		36		(55	)		8,429
Federal government agencies		6,926		1		(2	)		6,925
Certificates of deposit		3,867		—		—			3,867
		96,933		277		(114	)		97,096
	$	308,082	$	618	$	(151	)	$	308,549

As of January 31, 2019
Short-term Investments:
Corporate bonds	$	227,287	$	24	$	(214	)	$	227,097
Municipal and pre-refunded municipal bonds		43,677		15		(18	)		43,674
Federal government agencies		1,458		—		—			1,458
Certificate of deposit		1,050		—		—			1,050
Commercial paper		2,979		—		—			2,979
Treasury bills		2,975		—		(1	)		2,974
		279,426		39		(233	)		279,232
Long-term Investments:
Corporate bonds		34,265		34		(63	)		34,236
Municipal and pre-refunded municipal bonds		7,554		7		(3	)		7,558
Mutual funds, held in rabbi trust		6,301		450		—			6,751
Federal government agencies		6,603		2		(1	)		6,604
Certificates of deposit		2,143		—		—			2,143
		56,866		493		(67	)		57,292
	$	336,292	$	532	$	(300	)	$	336,524

Proceeds from the sales and maturities of available-for-sale securities were $428,508, $267,072 and $243,818 in fiscal 2020, 2019 and 2018, respectively. The Company included in “Interest income,” in the Consolidated Statements of Income, a net realized gain of $39 during fiscal 2020, and net realized losses of $22 and $35 during fiscal 2019 and 2018, respectively. Amortization of discounts and premiums, net, resulted in a reduction of “Interest income” of $706, $1,695 and $2,588 for fiscal 2020, 2019 and 2018, respectively. Mutual funds represent assets held in an irrevocable rabbi trust for the Company’s Non-qualified Deferred Compensation Plan

(“NQDC”). These assets are a source of funds to match the funding obligations to participants in the NQDC but are subject to the Company’s general creditors. The Company elected the fair value option for financial assets for the mutual funds held in the rabbi trust resulting in all unrealized gains and losses being recorded in “Interest income” in the Consolidated Statements of Income.

The following tables show the gross unrealized losses and fair value of the Company’s marketable securities with unrealized losses that are not deemed to be other-than-temporarily impaired aggregated by the length of time that individual securities have been in a continuous unrealized loss position, at January 31, 2020 and 2019, respectively.

	January 31, 2020
	Less Than 12 Months					12 Months or Greater				Total
Description of Securities	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate bonds	$	60,067	$	(66	)	$	—	$	—	$	60,067	$	(66	)
Municipal and pre-refunded municipal bonds		24,975		(28	)		—		—		24,975		(28	)
Mutual funds, held in rabbi trust		5,395		(55	)						5,395		(55	)
Federal government agencies		3,009		(2	)		—		—		3,009		(2	)
Total	$	93,446	$	(151	)	$	—	$	—	$	93,446	$	(151	)

	January 31, 2019
	Less Than 12 Months					12 Months or Greater					Total
Description of Securities	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate bonds	$	177,932	$	(160	)	$	38,201	$	(117	)	$	216,133	$	(277	)
Municipal and pre-refunded municipal bonds		20,732		(13	)		4,907		(8	)		25,639		(21	)
Federal government agencies		3,315		(1	)		—		—			3,315		(1	)
Treasury bills		2,974		(1	)		—		—			2,974		(1	)
Total	$	204,953	$	(175	)	$	43,108	$	(125	)	$	248,061	$	(300	)

As of January 31, 2020 and 2019, there were a total of 83 and 362 securities with unrealized loss positions within the Company’s portfolio, respectively.