CASH, CASH EQUIVALENTS AND INVESTMENTS - UNRESTRICTED AND RESTRICTED (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Restricted Cash and Cash Equivalent Item [Line Items]
Cash and cash equivalents	$ 328	$ 287
Investments	50	0
Total restricted cash, cash equivalents and investments	1,164	1,694
Collateral for workers' compensation claims	116	128
Total	1,658	2,109
Payroll funds collected
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	941	1,424
Collateral for health benefits claims
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	139	145
Collateral for workers' compensation claims
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	44	45
Collateral for workers' compensation claims	116	128
Trust for our ASO Users
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	40	79
Other security deposits
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	0	1
Cash and cash equivalents
Restricted Cash and Cash Equivalent Item [Line Items]
Cash and cash equivalents	328	287
Investments	0	0
Total restricted cash, cash equivalents and investments	1,054	1,586
Total	1,382	1,902
Cash and cash equivalents \| Payroll funds collected
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	941	1,424
Cash and cash equivalents \| Collateral for health benefits claims
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	38	37
Cash and cash equivalents \| Collateral for workers' compensation claims
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	35	45
Collateral for workers' compensation claims	0	29
Cash and cash equivalents \| Trust for our ASO Users
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	40	79
Cash and cash equivalents \| Other security deposits
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	0	1
Available-for-sale marketable securities
Restricted Cash and Cash Equivalent Item [Line Items]
Cash and cash equivalents	0	0
Investments	50	0
Total restricted cash, cash equivalents and investments	110	108
Total	276	207
Available-for-sale marketable securities \| Payroll funds collected
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	0	0
Available-for-sale marketable securities \| Collateral for health benefits claims
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	101	108
Available-for-sale marketable securities \| Collateral for workers' compensation claims
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	9	0
Collateral for workers' compensation claims	116	99
Available-for-sale marketable securities \| Trust for our ASO Users
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	0	0
Available-for-sale marketable securities \| Other security deposits
Restricted Cash and Cash Equivalent Item [Line Items]
Total restricted cash, cash equivalents and investments	$ 0	$ 0

Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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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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The current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal.

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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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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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