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Held for Sale and Discontinued Operations - Earnings Per Share for Discontinued Operations (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021
Basic and diluted earnings per share numerators (in millions): |  |  |  |
Net income (loss) | $ (169.2) | $ 138.5 | $ (135.8) | $ 63.2
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent | (175.1) | 137.4 | (145.3) | 72.5
Total gain (loss) from discontinued operations attributable to White Mountains’s common shareholders | (6.4) | (1.1) | (10.1) | 10.4
Allocation of earnings to participating restricted common shares | 2.2 | (1.7) | 1.6 | (0.9)
Basic and diluted earnings (losses) per share numerators | $ (172.9) | $ 135.7 | $ (143.7) | $ 71.6
Basic earnings per share denominators (in thousands): |  |  |  |
Total average common shares outstanding during the period (in shares) | 2,979,000 | 3,107,800 | 2,992,500 | 3,104,000
Average unvested restricted common shares (in shares) | (38,300) | (37,800) | (33,900) | (35,100)
Basic earnings (losses) per share denominator (in shares) | 2,940,700 | 3,070,000 | 2,958,600 | 3,068,900
Diluted earnings per share denominator (in thousands): |  |  |  |
Total average common shares outstanding during the period (in shares) | 2,979,000 | 3,107,800 | 2,992,500 | 3,104,000
Average unvested restricted common shares (in shares) | (38,300) | (37,800) | (33,900) | (35,100)
Diluted earnings (losses) per share denominator (in shares) | 2,940,700 | 3,070,000 | 2,958,600 | 3,068,900
Discontinued operations (in usd per share) | $ 1.98 | $ 0.35 | $ 3.17 | $ (3.00)
Discontinued operations (in usd per share) | $ 1.98 | $ 0.35 | $ 3.17 | $ (3.00)
Discontinued Operations |  |  |  |
Basic and diluted earnings per share numerators (in millions): |  |  |  |
Net income (loss) | $ (169.2) | $ 138.5 | $ (135.8) | $ 63.2
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent | (216.6) | 131.4 | (228.7) | 32.4
Less: net (income) loss from continuing operations attributable to non-controlling interests | 41.5 | 6.0 | 83.4 | 40.1
Total gain (loss) from discontinued operations attributable to White Mountains’s common shareholders | 5.9 | 1.1 | 9.5 | (9.3)
Allocation of earnings to participating restricted common shares | (0.1) | 0.0 | (0.1) | 0.1
Basic and diluted earnings (losses) per share numerators | $ 5.8 | $ 1.1 | $ 9.4 | $ (9.2)
Basic earnings per share denominators (in thousands): |  |  |  |
Total average common shares outstanding during the period (in shares) | 2,979,000 | 3,107,800 | 2,992,500 | 3,104,000
Average unvested restricted common shares (in shares) | (38,300) | (37,800) | (33,900) | (35,100)
Basic earnings (losses) per share denominator (in shares) | 2,940,700 | 3,070,000 | 2,958,600 | 3,068,900
Diluted earnings per share denominator (in thousands): |  |  |  |
Total average common shares outstanding during the period (in shares) | 2,979,000 | 3,107,800 | 2,992,500 | 3,104,000
Average unvested restricted common shares (in shares) | (38,300) | (37,800) | (33,900) | (35,100)
Diluted earnings (losses) per share denominator (in shares) | 2,940,700 | 3,070,000 | 2,958,600 | 3,068,900
Discontinued operations (in usd per share) | $ 1.98 | $ 0.35 | $ 3.17 | $ (3.00)

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