CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2025 |
Mar. 31, 2024 |
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| Statement of Comprehensive Income [Abstract] | ||
| Net income (loss) attributable to White Mountains’s common shareholders | $ 33.9 | $ 236.4 |
| Other comprehensive income (loss), net of tax | 2.0 | (0.3) |
| Comprehensive income (loss) | 35.9 | 236.1 |
| Other comprehensive (income) loss attributable to noncontrolling interests | (0.8) | 0.1 |
| Comprehensive income (loss) attributable to White Mountains’s common shareholders | $ 35.1 | $ 236.2 |
| Earnings (loss) per share attributable to White Mountains’s common shareholders: | ||
| Basic earnings (loss) per share (in dollars per share) | $ 13.19 | $ 92.33 |
| Diluted earnings (loss) per share (in dollars per share) | 13.19 | 92.33 |
| Dividends declared per White Mountains’s common share (in usd per share) | 1.00 | 1.00 |
| Dividends paid per White Mountains’s common share (in usd per share) | $ 1.00 | $ 1.00 |
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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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