Investment Securities Available-for-Sale (Schedule of Investment Securities) (Details) - USD ($) $ in Thousands	Aug. 30, 2025	May 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 999,139	$ 892,927
Unrealized Gains	2,359	133
Unrealized Losses	23	352
Estimated Fair Value	1,001,475	892,708
Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	22,072	21,695
Unrealized Gains	68	3
Unrealized Losses	0	0
Estimated Fair Value	22,140	21,698
Commercial Paper [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	81,527	90,880
Unrealized Gains	0	0
Unrealized Losses	23	50
Estimated Fair Value	81,504	90,830
Corporate Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	536,273	431,378
Unrealized Gains	2,120	130
Unrealized Losses	0	0
Estimated Fair Value	538,393	431,508
Certificates of Deposits [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,960	5,200
Unrealized Gains	8	0
Unrealized Losses	0	6
Estimated Fair Value	4,968	5,194
US Government and Agency Obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	245,019	240,655
Unrealized Gains	65	0
Unrealized Losses	0	260
Estimated Fair Value	245,084	240,395
Treasury Bills [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	109,288	103,119
Unrealized Gains	98	0
Unrealized Losses	0	36
Estimated Fair Value	$ 109,386	$ 103,083

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), clasified as current.

No definition available.

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

+ References

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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