SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT
Revenues (including realized gains and losses)	$ 626.6	$ 574.1	$ 489.3	$ 627.4	$ 566.4	$ 697.4	$ 542.3	$ 629.7	$ 2,317.4	$ 2,435.7	$ 2,173.1
Expenses	492.4	518.8	485.7	475.6	617.2	562.3	504.7	488.8	1,972.5	2,172.9	2,075.1
Pre-tax loss	134.2	55.3	3.6	151.8	(50.8)	135.1	37.6	140.9	344.9	262.8	98.0
Income tax (expense) benefit	(27.4)	(8.2)	0.6	(41.6)	101.0	(47.8)	(6.4)	(31.1)	(76.6)	15.7	110.0
Net income from continuing operations	106.8	47.1	4.2	110.2	50.2	87.3	31.2	109.8	268.3	278.5	208.0
Net income attributable to White Mountains’ common shareholders	117.9	57.2	26.3	120.4	68.2	19.1	26.1	94.0	321.8	207.4	767.9
Comprehensive income attributable to White Mountains’ common shareholders									242.0	302.6	686.2
Computation of net income (loss) available to common shareholders:
Net income attributable to White Mountains’ common shareholders	117.9	57.2	26.3	120.4	68.2	19.1	26.1	94.0	321.8	207.4	767.9
White Mountains Insurance Group Ltd.
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT
Revenues (including realized gains and losses)									1.2	20.8	6.4
Expenses									39.0	32.4	51.7
Pre-tax loss									(37.8)	(11.6)	(45.3)
Income tax (expense) benefit									(0.1)	(0.3)	6.5
Net income from continuing operations									(37.9)	(11.9)	(38.8)
Equity in earnings (losses) from consolidated and unconsolidated affiliates									359.7	219.3	806.7
Net income attributable to White Mountains’ common shareholders									321.8	207.4	767.9
Other comprehensive income (loss), after-tax									(79.8)	95.2	(81.7)
Comprehensive income attributable to White Mountains’ common shareholders									242.0	302.6	686.2
Computation of net income (loss) available to common shareholders:
Net income attributable to White Mountains’ common shareholders									$ 321.8	$ 207.4	$ 767.9

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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