Summary of Significant Accounting Policies (Details) - EBP 003 |
12 Months Ended | |
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Dec. 31, 2025
USD ($)
trust
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Dec. 31, 2024
USD ($)
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| EBP, Accounting Policy [Line Items] | ||
| Investments | $ 8,041,513,805 | $ 7,370,796,680 |
| Percentage of investments held by the master trust | 13.00% | 18.00% |
| Investments at fair value | $ 4,257,564,211 | $ 3,830,577,283 |
| Number of common collective trusts | trust | 4 | |
| Participant paid monthly recordkeeping fee | $ 1.63 | |
| Participant paid yearly recordkeeping fee | 19.50 | |
| Participant paid transaction fees for certain in-service withdrawals and distribution requests | 25 | |
| Participant paid new loan request fee | 50 | |
| Amounts allocated to withdrawing participants | 1,184,120 | 894,572 |
| Common collective trusts | ||
| EBP, Accounting Policy [Line Items] | ||
| Investments at fair value | 4,254,272,029 | 3,825,125,899 |
| Master Trust - Commingled Funds | Marsh common stock | ||
| EBP, Accounting Policy [Line Items] | ||
| Investments | $ 569,666,803 | $ 722,475,231 |
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- Definition EBP, Administrative Cost, Participant Paid Monthly Recordkeeping Fee No definition available.
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- Definition EBP, Administrative Cost, Participant Paid New Loan Request Fee No definition available.
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- Definition EBP, Administrative Cost, Participant Paid Withdrawal And Distribution Transaction Fee No definition available.
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- Definition EBP, Administrative Cost, Participant Paid Yearly Recordkeeping Fee No definition available.
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- Definition EBP, Number of Common Collective Trusts No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of investment in common stock of employer of participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), to total plan assets. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of investment held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, derivative, investment measured at net asset value per share as practical expedient, and insurance contract not meeting fully-benefit responsive investment criteria. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset allocated, but not yet paid, to participant electing to withdraw from employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) to reconcile net asset available for benefit per financial statement to Form 5500 caption. Form 5500 is form provided by Department of the Treasury, Internal Revenue Service (IRS); Department of Labor (DOL), Employee Benefit Security Administration (EBSA); and Pension Benefit Guaranty Corporation (PBGC). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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