SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Assets
Cash Including Restricted Cash	$ 179,300,000	$ 261,700,000
Fixed maturity investments, at fair value	2,639,700,000	2,422,000,000
Short-term investments, at amortized cost	211,300,000	376,800,000
Other assets	318,700,000	348,700,000
Total assets	10,284,500,000	10,455,700,000
Liabilities
Debt	442,400,000	343,100,000
Payable to subsidiary (2)	2.4
Other liabilities	264,700,000	278,400,000
Total liabilities	5,916,500,000	5,917,300,000
White Mountains’s common shareholders’ equity	4,368,000,000	4,538,400,000
Total liabilities and equity	10,284,500,000	10,455,700,000
White Mountains Insurance Group Ltd.
Assets
Cash Including Restricted Cash	300,000	200,000
Short-term investments, at amortized cost	23,400,000	31,000,000
Other assets	6,300,000	200,000
Investments in consolidated and unconsolidated affiliates	4,350,900,000	4,118,500,000
Total assets	4,380,900,000	4,149,900,000
Liabilities
Debt	50,000,000	0
Payable to subsidiary (2)	400,000,000	161,600,000
Other liabilities	17,700,000	(7,400,000)
Total liabilities	467,700,000	154,200,000
White Mountains’s common shareholders’ equity	3,913,200,000	3,995,700,000
Total liabilities and equity	$ 4,380,900,000	$ 4,149,900,000