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Commitments, Contingencies and Off-Balance Sheet Arrangements - Outstanding Letters of Credit, Financial Guarantees and Funding Commitments (Detail) $ in Millions | 12 Months Ended
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Dec. 31, 2024 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Maximum Exposure | $ 23.0
Liability Recorded | $ 12.0
Credit Support Under Letters of Credit for Deductibles Due by Us on Our Own Insurance Coverage's Expires After 2028 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | None
Maximum Exposure | $ 9.2
Liability Recorded | $ 12.0
Credit Enhancement Under Letters of Credit for Our Captive Insurance Operations to Meet Minimum Statutory Capital Requirement's Expires After 2028 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | Reimbursement of LOC fees
Maximum Exposure | $ 13.0
Collateral Related To Claim Funds Held in a Fiduciary Capacity by a Recent Acquisition Expires 2028 [Member] |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |
Collateral | None
Compensation to Us | None
Maximum Exposure | $ 0.8

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