Annual report pursuant to Section 13 and 15(d)

Description of Business, Basis of Presentation, and Significant Accounting Policies (Narrative) (Details)

v3.24.2
Description of Business, Basis of Presentation, and Significant Accounting Policies (Narrative) (Details)
 12 Months Ended
May 31, 2024
USD ($)
Item
Segment
May 31, 2023
USD ($)
Item
May 31, 2022
USD ($)
Item
Accounting Policies [Line Items]      
Number of reportable segments | Segment 1    
Revision increased net cash provided by operating activities   $ 6,800,000 $ 84,200,000
Revision decreased net cash provided by investing activities   6,800,000 84,200,000
Cash and cash equivalents $ 1,468,900,000 1,222,000,000 [1] 370,000,000 [1]
Allowance for credit losses 21,300,000 20,500,000  
Advance collections 700,000 12,500,000  
Goodwill 1,882,700,000 1,834,000,000 1,831,500,000
Goodwill, impairment loss 0 0 0
Impairment of intangible assets with indefinite useful lives 0 0 0
Impairment of long-lived assets 0 0 0
Realized gains or losses from foreign exchange transactions 0 0 0
Impairment loss, assets recognized from the costs to obtain and fufill contracts 0 0 0
Workers' compensation insurance costs in current liabilities 74,100,000 64,300,000  
Workers' compensation insurance costs in long-term liabilities 144,500,000 131,500,000  
Maximum individual health insurance claims liability 500,000 500,000  
PEO accrued health insurance and dental and vision plan reserves in current liabilities 50,600,000 47,000,000  
Operating lease, impairment loss $ 0 0 $ 0
Accounting Standards Update 2021-08 [Member]      
Accounting Policies [Line Items]      
Change in accounting principle, accounting standards update, adoption date Jun. 01, 2023    
Change in accounting principle, accounting standards update, adopted [true false] true    
Change in accounting principle, accounting standards update, immaterial effect [true false] true    
Trade Receivables [Member]      
Accounting Policies [Line Items]      
Receivables $ 141,300,000 287,000,000  
Purchased Receivables [Member]      
Accounting Policies [Line Items]      
Receivables $ 939,600,000 $ 606,800,000  
Minimum [Member]      
Accounting Policies [Line Items]      
Payroll funding fees average collection period 40 days    
Processing fee average collection period 5 days    
Minimum [Member] | Finite Lived Assets [Member]      
Accounting Policies [Line Items]      
Amortization period 3 years    
Minimum [Member] | Software [Member]      
Accounting Policies [Line Items]      
Estimated useful lives 3 years    
Minimum [Member] | Software Development [Member]      
Accounting Policies [Line Items]      
Estimated useful lives 12 years    
Maximum [Member]      
Accounting Policies [Line Items]      
Payroll funding fees average collection period 60 days    
Processing fee average collection period 15 days    
Maximum [Member] | Finite Lived Assets [Member]      
Accounting Policies [Line Items]      
Amortization period 12 years    
Maximum [Member] | Software [Member]      
Accounting Policies [Line Items]      
Estimated useful lives 5 years    
Revenue [Member]      
Accounting Policies [Line Items]      
Number of clients creating a credit concentration | Item 0 0 0
Accounts And Unbilled Receivables [Member]      
Accounting Policies [Line Items]      
Number of clients creating a credit concentration | Item 0 0  
INDIA [Member] | Long Lived Assets [Member] | Geographic Concentration Risk [Member] | Maximum [Member]      
Accounting Policies [Line Items]      
Concentration percentage 1.00% 1.00%  
Europe [Member] | Revenue [Member] | Geographic Concentration Risk [Member]      
Accounting Policies [Line Items]      
Concentration percentage 1.00% 1.00% 1.00%
Europe [Member] | Long Lived Assets [Member] | Geographic Concentration Risk [Member]      
Accounting Policies [Line Items]      
Concentration percentage 6.00% 6.00%  
PEO Aggregate Claims Exceeding $1.0M [Member] | Minimum [Member]      
Accounting Policies [Line Items]      
Individual workers' compensation claims liability $ 1,000,000 $ 1,000,000  
PEO Aggregate Claims Exceeding $1.0M [Member] | Maximum [Member]      
Accounting Policies [Line Items]      
Maximum individual workers' compensation claims liability 1,000,000 2,000,000  
PEO And Insurance Solutions [Member]      
Accounting Policies [Line Items]      
Cash and cash equivalents $ 171,700,000 $ 291,300,000  
[1] The consolidated statement of cash flows for the fiscal years ended May 31, 2023 and May 31, 2022 include revisions to previously reported amounts related to the presentation of cash flows associated with short-term receivables purchased from the Company’s clients under non-recourse arrangements, net of funding reserves. See Note A for further discussion on the revision.