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Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2024
Accounting Policies [Abstract] |
Activity and balances related to incurred but not paid workers' compensation claims | The following table provides the activity and balances related to incurred but not paid workers’ compensation claims:
| Year Ended December 31,
(in millions) | 2024 |  | 2023
Beginning balance, January 1, | $ | 220 |  |  | $ | 229 |
Accrued claims, net | 65 |  |  | 61 |
Present value discount, net of accretion | (12) |  |  | (13) |
Paid claims | (69) |  |  | (57) |
Ending balance | $ | 204 |  |  | $ | 220 |
Current portion of accrued claims | $ | 69 |  |  | $ | 57 |
Long-term portion of accrued claims | 135 |  |  | 163 |
Total accrued claims | $ | 204 |  |  | $ | 220 |
Disaggregation of Revenue [Table Text Block] | Our revenue for our PEO HR Outsourcing Solutions by geographic region and for our other products and services offerings are as follows:
| Year Ended December 31,
(in millions) | 2024 | 2023 | 2022
Northeast | $ | 1,801 |  | $ | 1,757 |  | $ | 1,625 |
Southeast | 926 |  | 907 |  | 796 |
Central | 1,195 |  | 1,170 |  | 1,045 |
Southwest | 1,245 |  | 1,250 |  | 1,163 |
West | 1,344 |  | 1,337 |  | 1,251 |
| 6,511 |  | 6,421 |  | 5,880 |
Other revenue | 70 |  | 65 |  | 59 |
Total revenue | $ | 6,581 |  | $ | 6,486 |  | $ | 5,939 |
Revenues Comprise of Gross Billings and WSEE Payroll Cost [Table] | Revenues are comprised of gross billings less WSEE payroll costs as follows:
| Year Ended December 31,
(in millions) | 2024 | 2023 | 2022
Gross billings | $ | 43,752 |  | $ | 43,141 |  | $ | 40,127 |
Less: WSEE payroll cost | 37,171 |  | 36,655 |  | 34,188 |
Revenues | $ | 6,581 |  | $ | 6,486 |  | $ | 5,939 |
Property, Plant and Equipment [Table Text Block] | Property and equipment, net consisted of the following:
(in millions) | December 31, 2024 | December 31, 2023
Land | $ | 6 |  | $ | 6 |
Buildings and improvements | 225 |  | 217 |
Computer hardware and software | 145 |  | 145 |
Software development costs | 149 |  | 137 |
Furniture, fixtures and other | 56 |  | 53 |
Property and equipment, gross | 581 |  | 558 |
Accumulated depreciation and amortization | (389) |  | (361) |
Property and equipment, net | $ | 192 |  | $ | 197 |
Depreciation, Depletion, and Amortization [Policy Text Block] | The estimated useful lives of property and equipment for purposes of computing depreciation are as follows:
| Useful Life
Buildings and improvements | 4 | — | 30 | years
Computer hardware and software | 2 | — | 5 | years
Software development costs | 3 | — | 5 | years
Furniture, fixtures and other | 5 | — | 7 | years

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