CASH, CASH EQUIVALENTS AND INVESTMENTS - UNRESTRICTED AND RESTRICTED (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	$ 349	$ 360
Total restricted cash, cash equivalents and investments	1,024	1,413
Collateral for workers' compensation claims	134	145
Total	1,507	1,918
Payroll funds collected
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	726	1,131
Collateral for health benefits claims
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	146	144
Collateral for workers' compensation claims
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	50	49
Collateral for workers' compensation claims	134	145
Trust for our HRIS Users
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	101	87
Other security deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	1	2
Cash and cash equivalents
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	349	360
Total restricted cash, cash equivalents and investments	911	1,303
Total	1,284	1,691
Cash and cash equivalents \| Payroll funds collected
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	726	1,131
Cash and cash equivalents \| Collateral for health benefits claims
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	33	34
Cash and cash equivalents \| Collateral for workers' compensation claims
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	50	49
Collateral for workers' compensation claims	24	28
Cash and cash equivalents \| Trust for our HRIS Users
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	101	87
Cash and cash equivalents \| Other security deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	1	2
Available-for-sale marketable securities
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	0	0
Total restricted cash, cash equivalents and investments	113	110
Total	223	227
Available-for-sale marketable securities \| Payroll funds collected
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	0
Available-for-sale marketable securities \| Collateral for health benefits claims
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	113	110
Available-for-sale marketable securities \| Collateral for workers' compensation claims
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	0	0
Collateral for workers' compensation claims	110	117
Available-for-sale marketable securities \| Trust for our HRIS Users
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	0	0
Available-for-sale marketable securities \| Other security deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Total restricted cash, cash equivalents and investments	$ 0	$ 0

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Cash and investments whose use in whole or in part is restricted for the long-term, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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The noncurrent cash, cash equivalents and investments that is restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits classified as long-term; that is not expected to be released from such existing restrictions within one year of the balance sheet date or operating cycle, whichever is longer. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes noncurrent cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

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