SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT
Revenues (including realized gains and losses)	$ 689.7us-gaap_Revenues	$ 589.4us-gaap_Revenues	$ 652.8us-gaap_Revenues	$ 578.3us-gaap_Revenues	$ 626.6us-gaap_Revenues	$ 574.1us-gaap_Revenues	$ 489.3us-gaap_Revenues	$ 627.4us-gaap_Revenues	$ 2,510.2us-gaap_Revenues	$ 2,317.4us-gaap_Revenues	$ 2,435.7us-gaap_Revenues
Expenses	643.5us-gaap_BenefitsLossesAndExpenses	555.0us-gaap_BenefitsLossesAndExpenses	543.8us-gaap_BenefitsLossesAndExpenses	466.2us-gaap_BenefitsLossesAndExpenses	492.4us-gaap_BenefitsLossesAndExpenses	518.8us-gaap_BenefitsLossesAndExpenses	485.7us-gaap_BenefitsLossesAndExpenses	475.6us-gaap_BenefitsLossesAndExpenses	2,208.5us-gaap_BenefitsLossesAndExpenses	1,972.5us-gaap_BenefitsLossesAndExpenses	2,172.9us-gaap_BenefitsLossesAndExpenses
Pre-tax loss	46.2	34.4	109.0	112.1	134.2	55.3	3.6	151.8	301.7	344.9	262.8
Income tax (expense) benefit	8.7us-gaap_IncomeTaxExpenseBenefit	(7.8)us-gaap_IncomeTaxExpenseBenefit	(23.9)us-gaap_IncomeTaxExpenseBenefit	(30.3)us-gaap_IncomeTaxExpenseBenefit	(27.4)us-gaap_IncomeTaxExpenseBenefit	(8.2)us-gaap_IncomeTaxExpenseBenefit	0.6us-gaap_IncomeTaxExpenseBenefit	(41.6)us-gaap_IncomeTaxExpenseBenefit	(53.3)us-gaap_IncomeTaxExpenseBenefit	(76.6)us-gaap_IncomeTaxExpenseBenefit	15.7us-gaap_IncomeTaxExpenseBenefit
Net income from continuing operations	54.9	26.6	85.1	81.8	106.8	47.1	4.2	110.2	248.4	268.3	278.5
Net loss from discontinued operations, net of tax	(12.2)	6.7	2.6	(0.5)	(0.3)	0.4	3.9	0.5	(1.8)	(42.1)	(24.0)
Net income attributable to White Mountains’s common shareholders	70.0	51.5	95.6	95.6	117.9	57.2	26.3	120.4	312.7	321.8	207.4
Comprehensive income attributable to White Mountains’ common shareholders									211.1us-gaap_ComprehensiveIncomeNetOfTax	242.0us-gaap_ComprehensiveIncomeNetOfTax	302.6us-gaap_ComprehensiveIncomeNetOfTax
Computation of net income (loss) available to common shareholders:
Net income attributable to White Mountains’s common shareholders	70.0	51.5	95.6	95.6	117.9	57.2	26.3	120.4	312.7	321.8	207.4
White Mountains Insurance Group Ltd.
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT
Revenues (including realized gains and losses)									0.3	1.2	20.8
Expenses									32.3	39.0	32.4
Pre-tax loss									(32.0)	(37.8)	(11.6)
Income tax (expense) benefit									0.9	(0.1)	(0.3)
Net income from continuing operations									(31.1)	(37.9)	(11.9)
Net loss from discontinued operations, net of tax									13.9	0	0
Equity in earnings (losses) from consolidated and unconsolidated affiliates									329.9	359.7	219.3
Net income attributable to White Mountains’s common shareholders									312.7	321.8	207.4
Other comprehensive income (loss), after-tax									(101.6)	(79.8)	95.2
Comprehensive income attributable to White Mountains’ common shareholders									211.1	242.0	302.6
Computation of net income (loss) available to common shareholders:
Net income attributable to White Mountains’s common shareholders									$ 312.7	$ 321.8	$ 207.4

The total amount of expense recognized during the period for future policy benefits, claims and claims adjustment costs, and for selling, general and administrative costs.

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