Segment Information (Tables)

9 Months Ended

Sep. 30, 2024

Segment Reporting [Abstract]

Schedule of segments

The following tables present the financial information for White Mountains’s segments for the three and nine months ended September 30, 2024 and 2023:

	Ark/WM Outrigger										Other Operations		Total
Millions	Ark		WM Outrigger Re		HG Global		Kudu		Bamboo
Three Months Ended September 30, 2024
Earned insurance premiums (1)	$	507.2	$	45.0	$	7.5	$	—	$	10.6	$	11.2	$	581.5
Net investment income (2)	21.3		3.0		6.0		17.2		.6		9.6		57.7
Net realized and unrealized    investment gains (losses) (2)	53.2		—		22.5		29.5		.7		29.7		135.6
Net realized and unrealized investment gains    (losses) from investment in MediaAlpha	—		—		—		—		—		88.2		88.2
Interest income from BAM Surplus Notes	—		—		7.9		—		—		—		7.9
Change in fair value of BAM Surplus Notes	—		—		15.8		—		—		—		15.8
Unrealized loss on deconsolidation    of BAM	—		—		(114.5)		—		—		—		(114.5)
Commission and fee revenues	—		—		—		—		42.7		4.1		46.8
Other revenues	3.7		—		—		.5		1.1		14.8		20.1
Total revenues	585.4		48.0		(54.8)		47.2		55.7		157.6		839.1
Loss and loss adjustment expenses	275.1		13.2		—		—		4.4		4.2		296.9
Acquisition expenses	83.3		13.0		1.9		—		3.7		4.5		106.4
Cost of sales	—		—		—		—		—		7.6		7.6
Broker commission expenses	—		—		—		—		15.9		—		15.9
General and administrative expenses	68.9		—		.3		3.6		16.2		32.9		121.9
Change in fair value of contingent consideration	34.2		—		—		—		—		—		34.2
Interest expense	4.9		—		5.8		5.7		—		.3		16.7
Total expenses	466.4		26.2		8.0		9.3		40.2		49.5		599.6
Pre-tax income (loss)	$	119.0	$	21.8	$	(62.8)	$	37.9	$	15.5	$	108.1	$	239.5

(1) Ark’s earned insurance premiums based on the location of Ark’s underwriting offices in the United Kingdom and Bermuda are $326.4 and $180.8.

(2) Bamboo’s net investment income and net realized and unrealized investment gains (losses) are included in other revenues in the consolidated statement of operations.

	Ark/WM Outrigger				HG Global						Other Operations
Millions	Ark		WM Outrigger Re		HG Global		BAM (1)		Kudu				Total
Three Months Ended September 30, 2023
Earned insurance premiums (2)	$	438.3	$	60.6	$	6.6	$	1.3	$	—	$	—	$	506.8
Net investment income	13.9		3.0		4.3		3.8		15.1		8.0		48.1
Net realized and unrealized    investment gains (losses)	(6.6)		—		(13.6)		(10.5)		11.2		8.0		(11.5)
Net realized and unrealized investment gains    (losses) from investment in MediaAlpha	—		—		—		—		—		(46.8)		(46.8)
Interest income (expense) from    BAM Surplus Notes	—		—		6.6		(6.6)		—		—		—
Commission and fee revenues	—		—		—		—		—		3.5		3.5
Other revenues	3.6		—		—		.7		—		15.2		19.5
Total revenues	449.2		63.6		3.9		(11.3)		26.3		(12.1)		519.6
Loss and loss adjustment expenses	258.5		7.3		—		—		—		—		265.8
Acquisition expenses	71.0		19.3		2.0		.1		—		—		92.4
Cost of sales	—		—		—		—		—		8.0		8.0
General and administrative expenses	35.3		.1		.5		17.0		4.5		42.2		99.6
Change in fair value of contingent    consideration	17.0		—		—		—		—		—		17.0
Interest expense	5.5		—		3.8		—		5.5		.9		15.7
Total expenses	387.3		26.7		6.3		17.1		10.0		51.1		498.5
Pre-tax income (loss)	$	61.9	$	36.9	$	(2.4)	$	(28.4)	$	16.3	$	(63.2)	$	21.1

(1) BAM manages its affairs on a statutory accounting basis. BAM’s statutory surplus includes the BAM Surplus Notes and is not reduced by accruals of interest expense on the BAM Surplus Notes. BAM’s statutory surplus is reduced only after a payment of principal or interest has been approved by the NYDFS.

(2) Ark’s earned insurance premiums based on the location of Ark’s underwriting offices in the United Kingdom and Bermuda are $273.6 and $164.7.

	Ark/WM Outrigger				HG Global								Other Operations
Millions	Ark		WM Outrigger Re		HG Global		BAM (1) (2)		Kudu		Bamboo				Total
Nine Months Ended September 30, 2024
Earned insurance premiums (3)	$	1,110.5	$	62.8	$	21.5	$	2.8	$	—	$	27.0	$	19.8	$	1,244.4
Net investment income (4)	57.6		8.9		17.3		8.8		50.1		1.5		27.9		172.1
Net realized and unrealized    investment gains (losses) (4)	84.1		—		13.2		(5.1)		77.5		.6		60.4		230.7
Net realized and unrealized investment gains    (losses) from investment in MediaAlpha	—		—		—		—		—		—		159.7		159.7
Interest income (expense) from    BAM Surplus Notes	—		—		21.1		(13.2)		—		—		—		7.9
Change in fair value of BAM Surplus Notes	—		—		15.8		—		—		—		—		15.8
Unrealized loss on deconsolidation    of BAM	—		—		(114.5)		—		—		—		—		(114.5)
Commission and fee revenues	—		—		—		—		—		97.3		11.1		108.4
Other revenues	9.6		—		—		1.1		.5		2.4		43.7		57.3
Total revenues	1,261.8		71.7		(25.6)		(5.6)		128.1		128.8		322.6		1,881.8
Loss and loss adjustment expenses	630.4		13.6		—		—		—		14.5		8.1		666.6
Acquisition expenses	212.9		17.9		5.9		.4		—		9.7		7.1		253.9
Cost of sales	—		—		—		—		—		—		22.2		22.2
Broker commission expenses	—		—		—		—		—		37.9		—		37.9
General and administrative expenses	153.9		.1		1.3		33.5		10.5		43.9		126.4		369.6
Change in fair value of contingent    consideration	47.5		—		—		—		—		—		—		47.5
Interest expense	15.0		—		13.4		—		16.7		—		1.6		46.7
Total expenses	1,059.7		31.6		20.6		33.9		27.2		106.0		165.4		1,444.4
Pre-tax income (loss)	$	202.1	$	40.1	$	(46.2)	$	(39.5)	$	100.9	$	22.8	$	157.2	$	437.4

(1) Effective July 1, 2024, White Mountains no longer consolidates BAM. For the period from January 1, 2024 through June 30, 2024, BAM’s results of operations are presented within the HG Global segment.

(2) BAM manages its affairs on a statutory accounting basis. BAM’s statutory surplus includes the BAM Surplus Notes and is not reduced by accruals of interest expense on the BAM Surplus Notes. BAM’s statutory surplus is reduced only after a payment of principal or interest has been approved by the NYDFS.

(3) Ark’s earned insurance premiums based on the location of Ark’s underwriting offices in the United Kingdom and Bermuda are $697.5 and $413.0.

(4) Bamboo’s net investment income and net realized and unrealized investment gains (losses) are included in other revenues in the consolidated statement of operations.

	Ark/WM Outrigger				HG Global						Other Operations
Millions	Ark		WM Outrigger Re		HG Global		BAM (1)		Kudu				Total
Nine Months Ended September 30, 2023
Earned insurance premiums (2)	$	971.9	$	75.4	$	19.4	$	3.9	$	—	$	—	$	1,070.6
Net investment income	33.5		7.7		12.4		10.5		44.0		22.0		130.1
Net realized and unrealized    investment gains (losses)	35.9		—		(11.4)		(5.6)		45.4		125.8		190.1
Net realized and unrealized investment gains    (losses) from investment in MediaAlpha	—		—		—		—		—		(38.9)		(38.9)
Interest income (expense) from    BAM Surplus Notes	—		—		19.7		(19.7)		—		—		—
Commission and fee revenues	—		—		—		—		—		10.0		10.0
Other revenues	(1.1)		—		—		2.0		—		67.1		68.0
Total revenues	1,040.2		83.1		40.1		(8.9)		89.4		186.0		1,429.9
Loss and loss adjustment expenses	573.2		7.9		—		—		—		—		581.1
Acquisition expenses	189.3		22.2		5.6		.7		—		—		217.8
Cost of sales	—		—		—		—		—		33.5		33.5
General and administrative expenses	105.3		.2		1.9		47.8		12.3		130.7		298.2
Change in fair value of contingent    consideration	16.8		—		—		—		—		—		16.8
Interest expense	15.7		—		10.8		—		15.5		2.9		44.9
Total expenses	900.3		30.3		18.3		48.5		27.8		167.1		1,192.3
Pre-tax income (loss)	$	139.9	$	52.8	$	21.8	$	(57.4)	$	61.6	$	18.9	$	237.6

(1) BAM manages its affairs on a statutory accounting basis. BAM’s statutory surplus includes the BAM Surplus Notes and is not reduced by accruals of interest expense on the BAM Surplus Notes. BAM’s statutory surplus is reduced only after a payment of principal or interest has been approved by the NYDFS.

(2) Ark’s earned insurance premiums based on the location of Ark’s underwriting offices in the United Kingdom and Bermuda are $588.3 and $383.6.