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SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT (Details 3) (USD $) | 3 Months Ended | 12 Months Ended |  | 1 Months Ended | 12 Months Ended |  | 1 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2012 | Sep. 30, 2012 | Jun. 30, 2012 | Mar. 31, 2012 | Dec. 31, 2011 | Sep. 30, 2011 | Jun. 30, 2011 | Mar. 31, 2011 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009 | Nov. 30, 2011 Lone Tree Insurance Group Ltd [Member] | Dec. 31, 2012 White Mountains Insurance Group Ltd. | Dec. 31, 2011 White Mountains Insurance Group Ltd. | Dec. 31, 2010 White Mountains Insurance Group Ltd. | Dec. 31, 2009 White Mountains Insurance Group Ltd. | Nov. 30, 2011 Fixed maturity investments Lone Tree Insurance Group Ltd [Member] | Nov. 30, 2011 Short-term investments Lone Tree Insurance Group Ltd [Member]
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common shares repurchased and retired during the period |  |  |  |  |  |  |  |  | 1,329,640 | 646,502 | 687,871 |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased and Retired During Period, Value |  |  |  |  |  |  |  |  | $ 669,100,000 | $ 253,000,000 | $ 225,500,000 |  |  |  |  |  |  |  |  |  |  |
Net Income (Loss) Available to Common Stockholders, Basic | 68,200,000 | 19,100,000 | 26,100,000 | 94,000,000 | 800,200,000 | (15,800,000) | 11,700,000 | (28,200,000) | 207,400,000 | 767,900,000 | 86,500,000 |  |  | 207,400,000 | [1] | 767,900,000 | [1] | 86,500,000 | [1] |  |  |
Charges (credits) to reconcile net income to net cash (used for) provided from operations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net realized and unrealized investment gains |  |  |  |  |  |  |  |  | (118,200,000) | (74,100,000) | (77,600,000) |  |  | (11,000,000) |  | (3,100,000) |  | 100,000 |  |  |  |
Undistributed current (earnings) losses from subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  | (219,300,000) | [1] | (806,700,000) | [1] | (128,200,000) | [1] |  |  |
Net federal income tax (payments) receipts |  |  |  |  |  |  |  |  | 17,500,000 | 12,500,000 | (47,000,000) |  |  |  |  |  |  |  |  |  |  |
Net change in other assets and liabilities, net |  |  |  |  |  |  |  |  | 151,000,000 | (229,000,000) | (89,500,000) |  |  | 12,100,000 |  | 13,700,000 |  | 27,900,000 |  |  |  |
Net cash (used for) provided from operations |  |  |  |  |  |  |  |  | (225,800,000) | (114,500,000) | 56,000,000 |  |  | (10,800,000) |  | (28,200,000) |  | (13,700,000) |  |  |  |
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net decrease in short-term investments |  |  |  |  |  |  |  |  | 145,300,000 | 174,500,000 | 475,600,000 |  |  | 63,300,000 | [2] | 267,300,000 | [2] | 166,500,000 | [2] |  |  |
Purchases of investment securities |  |  |  |  |  |  |  |  |  |  |  |  |  | (706,200,000) | [2] | (237,300,000) | [2] | (5,800,000) | [2] |  |  |
Sales and maturities of investment securities |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,009,700,000 | [3] | 59,000,000 | [3] | 0 | [3] |  |  |
Issuance of debt (to) from subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  | (121,000,000) |  | 0 |  | 86,800,000 |  |  |  |
Repayment of debt (to) from subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  | 28,500,000 | [2] | 192,500,000 | [2] | 0 | [2] |  |  |
Payments to subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  | (663,000,000) | [3] | 0 | [3] | 0 | [3] |  |  |
Distributions from subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  | 7,200,000 |  | 0 |  |  |  |
Net change in unsettled investment purchases and sales |  |  |  |  |  |  |  |  | (22,400,000) | 47,000,000 | 1,600,000 |  |  |  |  |  |  |  |  |  |  |
Net cash provided from investing activities |  |  |  |  |  |  |  |  | 829,600,000 | 799,600,000 | 485,300,000 |  |  | 611,300,000 |  | 288,700,000 |  | 247,500,000 |  |  |  |
Draw down of revolving line of credit |  |  |  |  |  |  |  |  | 150,000,000 | 0 | 0 |  |  | 150,000,000 |  | 0 |  | 0 |  |  |  |
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayment of debt |  |  |  |  |  |  |  |  | (75,000,000) | 0 | (14,000,000) |  |  | (75,000,000) |  | 0 |  | 0 |  |  |  |
Proceeds from issuances of common shares |  |  |  |  |  |  |  |  | 0 | 900,000 | 700,000 |  |  | 0 |  | 900,000 |  | 700,000 |  |  |  |
Repurchases and retirement of common shares |  |  |  |  |  |  |  |  | (669,100,000) | (253,000,000) | (225,600,000) |  |  | (669,100,000) | [3] | (253,000,000) | [3] | (225,600,000) | [3] |  |  |
Dividends paid on common shares |  |  |  |  |  |  |  |  | (6,600,000) | (8,000,000) | (8,800,000) |  |  | (6,600,000) |  | (8,000,000) |  | (8,800,000) |  |  |  |
Net cash used for financing activities |  |  |  |  |  |  |  |  | (648,200,000) | (460,200,000) | (550,200,000) |  |  | (600,700,000) |  | (260,100,000) |  | (233,700,000) |  |  |  |
Net change in cash during the period |  |  |  |  |  |  |  |  | (41,300,000) | 223,400,000 | (800,000) |  |  | (200,000) |  | 400,000 |  | 100,000 |  |  |  |
Cash balance at beginning of year | 212,600,000 |  |  |  | 251,900,000 |  |  |  | 212,600,000 | 251,900,000 | 103,600,000 | 119,900,000 |  | 500,000 |  | 700,000 |  | 300,000 |  | 200,000 |  |
Cash balance at end of year | 212,600,000 |  |  |  | 251,900,000 |  |  |  | 212,600,000 | 251,900,000 | 103,600,000 | 119,900,000 |  | 500,000 |  | 700,000 |  | 300,000 |  | 200,000 |  |
Noncash investments acquired |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 | 284.7
Noncash payables acquired |  |  |  |  |  |  |  |  |  |  |  |  | $ 417.5 |  |  |  |  |  |  |  |  |
[1] | n 2011, the Company revised the presentation of net income attributable to White Mountains’ common shareholders and undistributed current earnings from subsidiaries to be net of non-controlling interests for all periods presented.
[2] | In November 2011, Lone Tree Insurance Group Ltd., a direct wholly-owned subsidiary of the Registrant, was liquidated into the Registrant. Significant non-cash balances that were transferred to the Registrant as part of the liquidation included fixed maturity investments of $1,146.9, short-term investments of $284.7 and a payable to subsidiary of $417.5
[3] | During 2012, the Company sold the majority of its fixed maturity investments and used the proceeds to (a) contribute $663.0 to its subsidiaries, the majority of which was used to fund HG Global and (b) repurchase 1,329,640 of its common shares for $669.1

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- Definition The amount of payables that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 32 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The net amount paid (received) by the reporting entity through acquisition or sale and maturities of short-term investments with an original maturity that is three months or less which qualify for treatment as an investing activity based on management's intention and intended by management to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3095-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3098-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 13 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3291-108585 + Details
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- Definition Cash outflow in the form of ordinary dividends to common shareholders, generally out of earnings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3291-108585 + Details
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- Definition The cash outflow associated with the purchase of all investments (debt, security, other) during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3213-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 15, 17 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition The cash inflow from the additional capital contribution to the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585 + Details
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- Definition The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with either short term or long term maturity that is collateralized (backed by pledge, mortgage or other lien in the entity's assets). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 19 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3255-108585 + Details
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- Definition The cash inflow associated with the sale, maturities, repayments and calls of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time). + References No definition available. + Details
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- Definition The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations. + References No definition available. + Details
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- Definition Number of shares that have been repurchased and retired during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 + Details
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- Definition The net change during the reporting period in accounts receivable on unsettled investment sales and accounts payable on unsettled investment purchases. + References No definition available. + Details
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