Segment Information (Tables)

9 Months Ended

Sep. 30, 2015

Segment Reporting [Abstract]

Financial information for White Mountains' segments

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

				HG Global/BAM
Millions	OneBeacon			HG		BAM			Other Operations			Total
Three Months Ended September 30, 2015
Earned insurance premiums	$	281.4		$	.6	$	.3		$	2.6		$	284.9
Net investment income	12.4			.5		1.1			2.8			16.8
Net investment income (loss) - surplus note interest	—			4.0		(4.0		)	—			—
Net realized and unrealized investment (losses) gains	(29.9		)	.6		1.7			(16.3		)	(43.9		)
Other revenue	3.9			—		.2			72.8			76.9
Total revenues	267.8			5.7		(.7		)	61.9			334.7
Losses and LAE	167.5			—		—			2.5			170.0
Insurance acquisition expenses	53.8			.1		.4			1.0			55.3
Other underwriting expenses	56.4			—		.1			—			56.5
General and administrative expenses	3.7			.4		9.4			129.1			142.6
Interest expense	3.2			—		—			1.7			4.9
Total expenses	284.6			.5		9.9			134.3			429.3
Pre-tax (loss) income	$	(16.8	)	$	5.2	$	(10.6	)	$	(72.4	)	$	(94.6	)

				HG Global/BAM
Millions	OneBeacon			HG		BAM			Other Operations			Total
Nine Months Ended September 30, 2015
Earned insurance premiums	$	887.3		$	1.7	$	.6		$	6.4		$	896.0
Net investment income	33.0			1.4		2.9			5.3			42.6
Net investment income (loss) - surplus note interest	—			11.9		(11.9		)	—			—
Net realized and unrealized investment (losses) gains	(29.7		)	.3		2.8			(7.3		)	(33.9		)
Other (loss) revenue	(.4		)	—		.5			225.3			225.4
Total revenues	890.2			15.3		(5.1		)	229.7			1,130.1
Losses and LAE	527.9			—		—			6.2			534.1
Insurance acquisition expenses	161.2			.3		1.8			2.8			166.1
Other underwriting expenses	165.2			—		.3			—			165.5
General and administrative expenses	12.0			1.2		26.3			314.6			354.1
Interest expense	9.7			—		—			3.8			13.5
Total expenses	876.0			1.5		28.4			327.4			1,233.3
Pre-tax income (loss)	$	14.2		$	13.8	$	(33.5	)	$	(97.7	)	$	(103.2	)

				HG Global/BAM
Millions	OneBeacon			HG			BAM			Other Operations			Total
Three Months Ended September 30, 2014
Earned insurance premiums	$	305.4		$	.4		$	.1		$	1.3		$	307.2
Net investment income	10.8			.4			1.4			1.2			13.8
Net investment income (loss) - surplus note interest	—			3.9			(3.9		)	—			—
Net realized and unrealized investment losses	(16.0		)	(.5		)	(1.4		)	(9.6		)	(27.5		)
Other revenue	1.3			—			.2			28.2			29.7
Total revenues	301.5			4.2			(3.6		)	21.1			323.2
Losses and LAE	185.2			—			—			.3			185.5
Insurance acquisition expenses	54.6			—			.5			.1			55.2
Other underwriting expenses	51.2			—			.1			—			51.3
General and administrative expenses	2.4			.4			8.9			51.3			63.0
Interest expense	3.2			—			—			.5			3.7
Total expenses	296.6			.4			9.5			52.2			358.7
Pre-tax income (loss)	$	4.9		$	3.8		$	(13.1	)	$	(31.1	)	$	(35.5	)

			HG Global/BAM
Millions	OneBeacon		HG		BAM			Other Operations			Total
Nine Months Ended September 30, 2014
Earned insurance premiums	$	872.8	$	.9	$	.3		$	5.1		$	879.1
Net investment income	33.4		1.0		4.2			6.1			44.7
Net investment income (loss) - surplus note    interest	—		11.8		(11.8		)	—			—
Net realized and unrealized investment gains	24.8		1.1		5.4			33.1			64.4
Other revenue (loss)	3.3		—		.5			56.5			60.3
Total revenues	934.3		14.8		(1.4		)	100.8			1,048.5
Losses and LAE	520.7		—		—			6.6			527.3
Insurance acquisition expenses	150.9		.2		1.4			.5			153.0
Other underwriting expenses	152.3		—		.3			—			152.6
General and administrative expenses	9.3		1.2		26.6			131.2			168.3
Interest expense	9.7		—		—			.9			10.6
Total expenses	842.9		1.4		28.3			139.2			1,011.8
Pre-tax income (loss)	$	91.4	$	13.4	$	(29.7	)	$	(38.4	)	$	36.7