v3.26.1
Fair Value Measurement - Summary of Fair Value Hierarchy of Plan's Assets (Details) - EBP 001 - USD ($)
Dec. 31, 2025
Dec. 31, 2024
EBP, Investment, Fair Value and NAV [Line Items]    
Total $ 141,660,140 $ 129,497,421
Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 5,124,246 3,945,197
McGrath RentCorp Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 24,299,502 26,105,823
Money Market Mutual Fund    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 314,896 535,032
Brokerage accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 10,530,126 8,817,301
Total assets held in fair value hierarchy    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 40,268,770 39,403,353
Collective investment trusts at NAV    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 101,391,370 90,094,068
Level 1 | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 5,124,246 3,945,197
Level 1 | McGrath RentCorp Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 24,299,502 26,105,823
Level 1 | Money Market Mutual Fund    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 314,896 535,032
Level 1 | Brokerage accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 10,530,126 8,817,301
Level 1 | Total assets held in fair value hierarchy    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 40,268,770 39,403,353
Level 2 | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 2 | McGrath RentCorp Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 2 | Money Market Mutual Fund    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 2 | Brokerage accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 2 | Total assets held in fair value hierarchy    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 3 | Mutual funds    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 3 | McGrath RentCorp Common Stock    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 3 | Money Market Mutual Fund    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 3 | Brokerage accounts    
EBP, Investment, Fair Value and NAV [Line Items]    
Total 0 0
Level 3 | Total assets held in fair value hierarchy    
EBP, Investment, Fair Value and NAV [Line Items]    
Total $ 0 $ 0