CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flows from operations:
Net income (loss)	$ 110.6	$ (16.8)
Charges (credits) to reconcile net income to net cash (used for) provided from operations:
Net realized and unrealized investment gains (losses)	(58.6)	9.2
Net income from discontinued operations	(0.1)	(2.5)
Deferred income tax expense (benefit)	26.3	(32.8)
Undistributed equity in earnings from unconsolidated affiliates, after-tax	(10.2)	(6.7)
Other operating items:
Net change in loss and loss adjustment expense reserves	(226.5)	(40.5)
Net change in reinsurance recoverable on paid and unpaid losses	40.2	86.1
Net change in unearned insurance and reinsurance premiums	214.9	115.7
Net change in funds held by ceding companies	(0.6)	22.0
Net change in variable annuity benefit guarantee liabilities	(220.0)	(55.3)
Net change in deferred acquisition costs	(10.0)	(6.0)
Net change in ceded unearned premiums	(54.4)	2.0
Net change in funds held under reinsurance treaties	1.3	(4.9)
Net change in insurance and reinsurance premiums receivable	(235.6)	(165.4)
Net change in ceded reinsurance payable	54.5	(1.5)
Net change in other assets and liabilities, net	35.8	(39.9)
Net cash used for operations - continuing operations	(332.4)	(137.3)
Net cash (used for) provided from operations - discontinued operations	(2.0)	7.7
Net cash used for operations	(334.4)	(129.6)
Cash flows from investing activities:
Net change in short-term investments	(88.1)	88.4
Sales of fixed maturity and convertible fixed maturity investments	2,450.2	1,040.7
Maturities, calls and paydowns of fixed maturity and convertible fixed maturity investments	194.9	460.5
Sales of common equity securities	22.2	58.0
Distributions and redemptions of other long-term investments	11.1	54.0
Purchases of other long-term investments	(6.1)	(6.9)
Contributions to discontinued operations		(56.4)
Purchases of common equity securities	(98.7)	(65.5)
Purchases of fixed maturity and convertible fixed maturity investments	(1,737.1)	(1,398.4)
Net change in unsettled investment purchases and sales	67.1	64.3
Net acquisitions of property and equipment	(0.6)	(2.2)
Net cash provided from investing activities - continuing operations	814.9	236.5
Net cash used for investing activities - discontinued operations		(3.5)
Net cash provided from investing activities	814.9	233.0
Cash flows from financing activities:
Cash dividends paid to the Company's common shareholders		(8.0)
Cash dividends paid to OneBeacon Ltd.'s noncontrolling common shareholders	(5.0)	(4.8)
Common shares repurchased	(485.8)	(86.1)
Net cash used for financing activities - continuing operations	(490.8)	(98.9)
Net cash provided from financing activities - discontinued operations	0
Net cash used for financing activities	(490.8)	(98.9)
Effect of exchange rate changes on cash	1.7	2.3
Net change in cash during the period	(6.6)	2.6
Net change in cash from discontinued operations	(2.0)	4.2
Cash reclassified from assets held for sale (net of cash sold of $3.5)	2.0
Cash balances at beginning of period (excludes restricted cash balances of $453.5 and $286.7)	251.9	148.1
Cash balances at end of period (excludes restricted cash balances of $ 360.1 and $297.6)	245.3	154.9
Supplemental cash flows information:
Interest paid	(12.8)	(12.8)
Net income tax payments to national governments	$ (8.7)	$ (10.8)

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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).