Segment Information (Schedule of Reportable Segment Performance Significant Expenses and Assets) (Parenthetical) (Detail) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
[2] | Mar. 31, 2025 |
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| Segment Reporting Information [Line Items] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Cash balance | $ 2,624.8 | $ 1,387.3 | |||||||||||||||||||||||||||||||||||||||||||||||||||||
| Total assets | 18,941.0 | $ 16,228.8 | |||||||||||||||||||||||||||||||||||||||||||||||||||||
| Eliminations | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Segment Reporting Information [Line Items] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Cash balance | (259.3) | $ (139.9) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
| Receivable from subsidiary | (19.5) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Total assets | (263.6) | [1] | $ (162.9) | (162.9) | |||||||||||||||||||||||||||||||||||||||||||||||||||
| Eliminations | Home Warranty | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Segment Reporting Information [Line Items] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Cash balance | $ (4.3) | $ (3.5) | |||||||||||||||||||||||||||||||||||||||||||||||||||||
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- Definition Amount of asset recognized for present right to economic benefit. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount due from parties in nontrade transactions, classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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. No definition available.
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- Details
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