Segment Information

3 Months Ended

Mar. 31, 2013

Segment Reporting [Abstract]

Segment Informartion

Segment Information

White Mountains has determined that its reportable segments are OneBeacon, Sirius Group, HG Global/BAM and Other Operations.

White Mountains has made its segment determination based on consideration of the following criteria: (i) the nature of the business activities of each of the Company’s subsidiaries and affiliates; (ii) the manner in which the Company’s subsidiaries and affiliates are organized; (iii) the existence of primary managers responsible for specific subsidiaries and affiliates; and (iv) the organization of information provided to the chief operating decision makers and the Board of Directors.

Significant intercompany transactions among White Mountains’ segments have been eliminated herein. Financial information for White Mountains’ segments follows:

					HG Global/BAM
Millions	OneBeacon		Sirius Group		HG			BAM			Other Operations			Total
Three Months Ended March 31, 2013
Earned insurance and reinsurance premiums	$	286.5	$	208.9	$	—		$	—		$	—		$	495.4
Net investment income	9.4		13.1		.3			1.1			4.6			28.5
Net investment income - surplus note income	—		—		10.1			(10.1		)	—			—
Net realized and unrealized investment    gains (losses)	28.4		13.1		(.2		)	(1.1		)	35.0			75.2
Other revenue	24.0		10.5		—			.1			(6.3		)	28.3
Total revenues	348.3		245.6		10.2			(10.0		)	33.3			627.4
Losses and loss adjustment expenses	148.9		95.4		—			—			—			244.3
Insurance and reinsurance acquisition expenses	54.8		43.3		—			.1			—			98.2
Other underwriting expenses	49.3		29.7		—			.1			—			79.1
General and administrative expenses	4.0		9.5		.3			8.2			21.8			43.8
Interest expense on debt	3.2		6.6		—			—			.4			10.2
Total expenses	260.2		184.5		.3			8.4			22.2			475.6
Pre-tax income (loss)	$	88.1	$	61.1	$	9.9		$	(18.4	)	$	11.1		$	151.8

Millions	OneBeacon		Sirius Group		Other Operations		Total
Three Months Ended March 31, 2012
Earned insurance and reinsurance premiums	$	271.8	$	226.2	$	—	$	498.0
Net investment income	14.7		17.1		10.0		41.8
Net realized and unrealized investment gains	29.8		13.7		15.1		58.6
Other revenue	.1		18.3		12.8		31.2
Total revenues	316.4		275.3		37.9		629.6
Losses and loss adjustment expenses	136.4		113.4		—		249.8
Insurance and reinsurance acquisition expenses	58.1		51.0		—		109.1
Other underwriting expenses	47.5		26.0		—		73.5
General and administrative expenses	2.7		18.9		23.9		45.5
Interest expense on debt	4.1		6.5		.3		10.9
Total expenses	248.8		215.8		24.2		488.8
Pre-tax income	$	67.6	$	59.5	$	13.7	$	140.8