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Other Balance Sheet Information (Tables) | 12 Months Ended
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Dec. 31, 2024
OtherBalanceSheetDisclosuresAbstract [Abstract] |
Summary of investments in cash, cash equivalents and marketable securities | The following table summarizes our cash and investments in cash equivalents and marketable securities held by investment managers and overnight investments:
| December 31, 2024 |  | December 31, 2023
(in millions) | Cash & Cash Equivalents | Marketable Securities | Total |  | Cash & Cash Equivalents | Marketable Securities | Total
Overnight holdings | $ | 931 |  | $ | — |  | $ | 931 |  |  | $ | 611 |  | $ | — |  | $ | 611 |
Investment holdings | 117 |  | 16 |  | 133 |  |  | 119 |  | 16 |  | 135 |
| 1,048 |  | 16 |  | 1,064 |  |  | 730 |  | 16 |  | 746 |
Cash in demand accounts | 27 |  | — |  | 27 |  |  | 27 |  | — |  | 27 |
Outstanding checks | (36) |  | — |  | (36) |  |  | (64) |  | — |  | (64) |
Total | $ | 1,039 |  | $ | 16 |  | $ | 1,055 |  |  | $ | 693 |  | $ | 16 |  | $ | 709 |
Restrictions on Cash and Cash Equivalents | Cash, Cash Equivalents, Restricted Cash, Funds Held for Clients, and Deposits – Workers’ Compensation The following table summarizes our cash, cash equivalents, restricted cash, funds held for clients, and deposits – workers’ compensation as reported in our Consolidated Statements of Cash Flows:
| Year Ended December 31, |
(in millions) | 2024 |  | 2023 |  | 2022 |
Supplemental schedule of cash and cash equivalents, restricted cash, funds held for clients, and deposits – workers’ compensation |
Cash and cash equivalents | $ | 693 |  |  | $ | 733 |  |  | $ | 576 |  |
Restricted cash | 57 |  |  | 50 |  |  | 47 |  |
Other current assets - funds held for clients(1) | 87 |  |  | 35 |  |  | 32 |  |
Deposits – workers’ compensation | 198 |  |  | 196 |  |  | 185 |  |
Cash, cash equivalents, restricted cash, funds held for clients, and deposits – workers’ compensation beginning of year | $ | 1,035 |  |  | $ | 1,014 |  |  | $ | 840 |  |
Cash and cash equivalents | $ | 1,039 |  |  | $ | 693 |  |  | $ | 733 |  |
Restricted cash | 69 |  |  | 57 |  |  | 50 |  |
Other current assets - funds held for clients(1) | 58 |  |  | 87 |  |  | 35 |  |
Deposits – workers’ compensation | 178 |  |  | 198 |  |  | 196 |  |
Cash, cash equivalents, restricted cash, funds held for clients, and , and deposits – workers’ compensation end of year | $ | 1,344 |  |  | $ | 1,035 |  |  | $ | 1,014 |  |
____________________________________ (1)Funds held for clients represent amounts held on behalf of our Traditional Payroll Solution customers that are restricted for the purpose of satisfying obligations to remit funds to clients’ employees and various tax authorities. Please read Note 1. “Accounting Policies,” for a discussion of our accounting policies for deposits — workers’ compensation and restricted cash.

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