CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operations:
Net income	$ 809.4	$ 139.5	$ 579.5
Charges (credits) to reconcile net income to net cash (used for) provided from operations:
Net realized and unrealized investment (gains) losses	(122.8)	(82.6)	(361.7)
Excess of fair value of acquired net assets over cost	(7.2)	(12.8)
Deferred income tax (benefit) expense	(80.6)	58.0	170.0
Undistributed equity in earnings from unconsolidated affiliates, after-tax	20.2	(9.9)	(24.3)
Net loss from discontinued operations	13.0	6.6	27.8
Net loss on sale of discontinued operation - AutoOne	19.2
Net gain on sale of discontinued operation - Esurance	(677.5)
Other operating items:
Net change in loss and loss adjustment expense reserves	35.2	(466.0)	(731.4)
Net change in reinsurance recoverable on paid and unpaid losses	(134.0)	361.8	306.2
Net change in unearned insurance and reinsurance premiums	(48.6)	(161.3)	(132.2)
Net change in ceded reinsurance premiums payable	(85.9)	120.1	(20.2)
Net change in ceded unearned insurance and reinsurance premiums	94.2	(89.8)	13.3
Net change in insurance and reinsurance premiums receivable	42.4	131.9	71.4
Net change in variable annuity benefit guarantee liabilities	158.3	229.5	(86.4)
Net change in deferred acquisition costs	(14.5)	57.9	25.4
Net change in funds held by ceding companies	11.6	53.7	62.9
Net change in funds held under reinsurance treaties	(42.3)	(85.1)	10.3
Net change in other assets and liabilities, net	(96.5)	(238.6)	27.5
Net cash (used for) provided from operations - continuing operations	(106.4)	12.9	(61.9)
Net cash (used for) provided from operations - discontinued operations	(8.1)	43.1	15.2
Net cash (used for) provided from operations	(114.5)	56.0	(46.7)
Cash flows from investing activities:
Net change in short-term investments	174.5	475.6	218.4
Sales of fixed maturity and convertible fixed maturity investments	3,481.9	2,447.8	2,121.9
Maturities, calls and paydowns of fixed maturity and convertible fixed maturity investments	1,163.6	1,744.1	1,206.9
Sales of common equity securities	237.8	167.5	300.8
Distributions and redemptions of other long-term investments	150.7	133.2	118.9
Sales of consolidated and unconsolidated affiliates, net of cash sold	1,010.6	188.3
Contributions to other long-term investments	(65.8)	(111.1)	(25.2)
Distributions from (contributions to) discontinued operations	28.7	(32.1)	(123.1)
Purchases of common equity securities	(297.8)	(273.6)	(190.1)
Purchases of fixed maturity and convertible fixed maturity investments	(5,200.6)	(4,217.7)	(3,296.5)
Purchases of consolidated and unconsolidated affiliates, net of cash acquired	(3.2)	(4.9)
Net change in unsettled investment purchases and sales	47.0	1.6	52.1
Net acquisitions of property and equipment	(5.5)	(5.8)	(7.6)
Net cash provided from investing activities - continuing operations	721.9	512.9	376.5
Net cash provided from (used for) investing activities - discontinued operations	77.7	(27.6)	(11.4)
Net cash provided from investing activities	799.6	485.3	365.1
Cash flows from financing activities:
Repayment of debt		(14.0)	(242.8)
Repurchase of debt	(161.6)	(197.3)	(63.1)
Settlement of interest rate swap associated with Mortgage Note			(7.5)
Capital lease obligation	23.1
Cash dividends paid to the Company's common shareholders	(8.0)	(8.8)	(8.9)
Cash dividends paid to OneBeacon Ltd.'s noncontrolling common shareholders	(42.8)	(75.9)	(19.6)
Cash dividends paid on SIG Preference Shares	(18.8)	(18.8)	(18.8)
Common shares repurchased	(253.0)	(225.6)	(0.4)
OneBeacon Ltd. common shares repurchased and retired		(10.5)
Proceeds from issuances of common shares	0.9	0.7	0.9
Net cash used for financing activities - continuing operations	(460.2)	(550.2)	(360.2)
Net cash provided from financing activities - discontinued operations	0
Net cash used for financing activities	(460.2)	(550.2)	(360.2)
Effect of exchange rate changes on cash	(1.5)	8.1	6.8
Net increase (decrease) in cash during year	223.4	(0.8)	(35.0)
Net decrease in cash from discontinued operations	(69.6)	(15.5)	(3.8)
Cash reclassified to assets held for sale	(5.5)
Cash balance at beginning of year (excludes restricted cash balances of $286.7, $217.1 and $225.7 and AutoOne cash of $4.7, $3.9 and $3.5)	103.6	119.9	158.7
Cash balance at end of year (excludes restricted cash balances of $453.5, $286.7and $217.1 and AutoOne cash of $0, $4.7 and $3.9)	$ 251.9	$ 103.6	$ 119.9

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).