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SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT (Details) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015
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CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |
Other long-term investments | $ 323.3 | $ 315.8
Assets |  |
Cash Including Restricted Cash | 149.8 | 173.0
Fixed maturity investments, at fair value | 4,250.2 | 2,630.2
Short-term investments, at amortized cost | 287.0 | 211.2
Other assets | 274.6 | 273.2
Total assets | 6,544.7 | 10,282.6
Liabilities |  |
Debt | 285.9 | 337.6
Other liabilities | 199.9 | 250.8
Total liabilities | 2,807.5 | 5,914.6
White Mountains’s common shareholders’ equity | 3,737.2 | 4,368.0
Total liabilities and equity | 6,544.7 | 10,282.6
White Mountains Insurance Group Ltd. |  |
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |
Other long-term investments | (1.2) |
Assets |  |
Cash Including Restricted Cash | 3.1 | 0.3
Fixed maturity investments, at fair value | 80.0 | 0.0
Short-term investments, at amortized cost | 12.5 | 23.4
Other assets | 1.4 | 6.3
Investments in consolidated and unconsolidated affiliates | 4,898.2 | 4,350.9
Total assets | 4,994.0 | 4,380.9
Liabilities |  |
Debt | 0.0 | 50.0
Payable to subsidiary (2) | 1,387.2 | 400.0
Other liabilities | 3.5 | 17.7
Total liabilities | 1,390.7 | 467.7
White Mountains’s common shareholders’ equity | 3,603.3 | 3,913.2
Total liabilities and equity | $ 4,994.0 | $ 4,380.9

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