CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Assets
Fixed maturity investments, at fair value	$ 5,248.7	$ 6,221.9
Short-term investments, at amortized cost (which approximates fair value)	618.4	846.0
Common equity securities, at fair value	919.2	755.0
Convertible fixed maturity investments, at fair value	145.5	143.8
Other long-term investments	292.5	301.3
Total investments	7,224.3	8,268.0
Cash (restricted: $360.0 and $453.5)	811.6	705.4
Reinsurance recoverable on unpaid losses	2,369.4	2,507.3
Reinsurance recoverable on paid losses	39.7	30.5
Insurance and reinsurance premiums receivable	747.0	489.2
Funds held by ceding companies	107.9	106.5
Investments in unconsolidated affiliates	337.5	275.3
Deferred acquisition costs	200.0	187.0
Deferred Income Tax Assets	504.6	536.9
Ceded unearned insurance and reinsurance premiums	135.2	87.3
Accrued investment income	54.1	51.4
Accounts receivable on unsettled investment sales	76.2	4.7
Other assets	673.0	681.9
Assets held for sale	0	132.6
Total assets	13,280.5	14,064.0
Liabilities
Loss and loss adjustment expense reserves	5,329.8	5,702.3
Unearned insurance and reinsurance premiums	1,065.4	846.9
Variable annuity benefit guarantee	661.8	768.5
Debt	677.6	677.5
Deferred tax liability	368.1	365.5
Accrued incentive compensation	113.6	187.9
Ceded reinsurance payable	175.6	134.6
Funds held under reinsurance treaties	47.7	42.9
Accounts payable on unsettled investment purchases	44.5	34.6
Other liabilities	461.9	527.8
Liabilities held for sale	0	107.6
Total liabilities	8,946.0	9,396.1
Equity
White Mountains' common shares at $1 par value per share - authorized 50,000,000 shares; issued and outstanding 6,630,318 and 7,577,855 shares	6.6	7.6
Paid-in surplus	1,102.2	1,253.7
Retained earnings	2,576.3	2,789.7
Accumulated other comprehensive income, after-tax:
Equity in net unrealized losses from investments in unconsolidated affiliates	27.0	0
Net unrealized foreign currency translation gains	39.5	46.1
Pension liability and other	(9.1)	(9.4)
Total White Mountains' common shareholders' equity	3,742.5	4,087.7
Noncontrolling interests
Noncontrolling interest - OneBeacon Ltd.	280.4	273.1
Noncontrolling interest - SIG Preference Shares	250.0	250.0
Noncontrolling interest - other	61.6	57.1
Total noncontrolling interests	592.0	580.2
Total equity	4,334.5	4,667.9
Total liabilities and equity	$ 13,280.5	$ 14,064.0