v3.26.1
Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis and Categorized using Fair Value Hierarchy (Detail) - USD ($)
$ in Thousands
May 31, 2026
May 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities $ 25,354 $ 24,323
Total marketable equity securities 174,400 135,400
U.S. Treasury and other government    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 25,231 24,200
Corporate bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 123 123
Fair Value, Measurements, Recurring    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 25,354 24,323
Total marketable equity securities 174,394 135,419
Assets (liabilities) at fair value 194,399 142,490
Fair Value, Measurements, Recurring | U.S. Treasury and other government    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 25,231 24,200
Fair Value, Measurements, Recurring | Corporate bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 123 123
Fair Value, Measurements, Recurring | Stocks | Foreign    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 370 1,265
Fair Value, Measurements, Recurring | Stocks | Domestic    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 5,213 8,642
Fair Value, Measurements, Recurring | Mutual funds | Foreign    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 49,082 38,943
Fair Value, Measurements, Recurring | Mutual funds | Domestic    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 119,729 86,569
Fair Value, Measurements, Recurring | Contingent consideration liability    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Contingent consideration (5,349) (17,252)
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 19,247 9,907
Assets (liabilities) at fair value 19,247 9,907
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Stocks | Foreign    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 370 1,265
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Stocks | Domestic    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 5,213 8,642
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Mutual funds | Domestic    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 13,664  
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 25,354 24,323
Total marketable equity securities 155,147 125,512
Assets (liabilities) at fair value 180,501 149,835
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury and other government    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 25,231 24,200
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate bonds    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total available-for-sale securities 123 123
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Mutual funds | Foreign    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 49,082 38,943
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Mutual funds | Domestic    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total marketable equity securities 106,065 86,569
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Assets (liabilities) at fair value (5,349) (17,252)
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Contingent consideration liability    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Contingent consideration $ (5,349) $ (17,252)