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SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT (Details 3) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |  |  |  |  |  |  |  |  |  |
Net income attributable to White Mountains’s common shareholders | $ (33,300,000) | $ 91,700,000 | $ 341,100,000 | $ 13,000,000 | $ 267,900,000 | $ (58,900,000) | $ 4,300,000 | $ 84,300,000 | $ 412,500,000 | $ 297,600,000 | $ 312,200,000
Charges (credits) to reconcile net income to net cash (used for) provided from operations: |  |  |  |  |  |  |  |  |  |  |
Net realized and unrealized investment gains |  |  |  |  |  |  |  |  | (10,300,000) | (225,400,000) | (78,500,000)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest | 6,800,000 | $ (61,900,000) | $ (358,600,000) | (1,100,000) | (19,600,000) | $ (6,500,000) | $ 500,000 | (71,300,000) | 300,000 | (78,700,000) | (260,600,000)
Net change in other assets and liabilities, net |  |  |  |  |  |  |  |  | (226,700,000) | 49,700,000 | (142,400,000)
Net Cash Provided by (Used in) Operating Activities, Continuing Operations |  |  |  |  |  |  |  |  | (130,600,000) | 119,700,000 | 69,900,000
Net cash (used for) provided from discontinued operations |  |  |  |  |  |  |  |  | (24,700,000) | 56,000,000 | 48,900,000
Net cash (used for) provided from operations |  |  |  |  |  |  |  |  | (155,300,000) | 175,700,000 | 118,800,000
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |
Net decrease in short-term investments |  |  |  |  |  |  |  |  | (70,100,000) | 140,000,000 | (138,000,000)
Net Cash Provided by (Used in) Investing Activities, Continuing Operations |  |  |  |  |  |  |  |  | 1,055,100,000 | 16,700,000 | (3,300,000)
Net cash provided from investing activities — discontinued operations |  |  |  |  |  |  |  |  | 221,700,000 | (5,400,000) | 51,200,000
Net cash provided from investing activities |  |  |  |  |  |  |  |  | 1,276,800,000 | 11,300,000 | 47,900,000
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |
Draw down of debt and revolving line of credit |  |  |  |  |  |  |  |  | 352,500,000 | 171,500,000 | 133,600,000
Repayment of debt and revolving line of credit |  |  |  |  |  |  |  |  | (404,600,000) | (76,100,000) | (65,200,000)
Proceeds from issuances of common shares |  |  |  |  |  |  |  |  | 3,700,000 | 0 | 0
Repurchases and retirement of common shares |  |  |  |  |  |  |  |  | (881,300,000) | (268,600,000) | (128,200,000)
Dividends paid on common shares |  |  |  |  |  |  |  |  | (5,400,000) | (6,000,000) | (6,200,000)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations |  |  |  |  |  |  |  |  | (942,200,000) | (203,000,000) | (65,100,000)
Net cash used for financing activities — discontinued operations |  |  |  |  |  |  |  |  | (200,000) | (11,600,000) | (64,500,000)
Net cash used for financing activities |  |  |  |  |  |  |  |  | (942,400,000) | (214,600,000) | (129,600,000)
Net change in cash during the period - continuing operations |  |  |  |  |  |  |  |  | (17,700,000) | (66,600,000) | 1,500,000
Cash balance at beginning of year |  |  |  | 167,200,000 |  |  |  | 232,700,000 | 167,200,000 | 232,700,000 | 233,500,000
Cash balance at end of year | 149,800,000 |  |  |  | 167,200,000 |  |  |  | 149,800,000 | 167,200,000 | 232,700,000
Interest Paid |  |  |  |  |  |  |  |  | (14,800,000) | (12,800,000) | (13,000,000)
OneBeacon Ltd. common shares repurchased and retired |  |  |  |  |  |  |  |  | (11,500,000) | (3,700,000) | (1,700,000)
White Mountains Insurance Group Ltd. |  |  |  |  |  |  |  |  |  |  |
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |  |  |  |  |  |  |  |  |  |
Payable to subsidiary (2) |  |  |  |  |  |  |  |  | 200,000.0 | 2,400,000.0 | 700,000.0
Transfer from Investments |  |  |  |  |  |  |  |  | 80,000,000.0 |  |
Net income attributable to White Mountains’s common shareholders |  |  |  |  |  |  |  |  | 412,500,000 | 297,600,000 | 312,200,000
Charges (credits) to reconcile net income to net cash (used for) provided from operations: |  |  |  |  |  |  |  |  |  |  |
Net realized and unrealized investment gains |  |  |  |  |  |  |  |  | 1,100,000 | 0 | (200,000)
Undistributed current earnings from subsidiaries |  |  |  |  |  |  |  |  | (482,200,000) | (352,500,000) | (329,400,000)
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  | 0 | 0 | (13,900,000)
Other non-cash reconciling items including restricted share and option amortization |  |  |  |  |  |  |  |  | 17,900,000 | (400,000) | 12,900,000
Net change in other assets and liabilities, net |  |  |  |  |  |  |  |  | (11,400,000) | 21,400,000 | (7,600,000)
Net Cash Provided by (Used in) Operating Activities, Continuing Operations |  |  |  |  |  |  |  |  | (62,100,000) | (33,900,000) | (26,000,000)
Net cash (used for) provided from discontinued operations |  |  |  |  |  |  |  |  | 0 | 0 | 13,900,000
Net cash (used for) provided from operations |  |  |  |  |  |  |  |  | (62,100,000) | (33,900,000) | (12,100,000)
Cash flows from investing activities: |  |  |  |  |  |  |  |  |  |  |
Net decrease in short-term investments |  |  |  |  |  |  |  |  | 10,900,000 | 7,600,000 | (29,600,000)
Purchases of investment securities |  |  |  |  |  |  |  |  | 0 | 0 | (7,600,000)
Sales and maturities of investment securities |  |  |  |  |  |  |  |  | 0 | 0 | 39,400,000
Issuance of debt (to) from subsidiaries |  |  |  |  |  |  |  |  | 992,000,000 | 271,000,000 | 144,600,000
Repayment of debt (to) from subsidiaries |  |  |  |  |  |  |  |  | (5,000,000) | (35,000,000) | (30,000,000)
Receipt of cash flow from discontinued operations |  |  |  |  |  |  |  |  | 0 | 0 | 13,900,000
Distributions from subsidiaries |  |  |  |  |  |  |  |  | 0 | 15,000,000 | 29,700,000
Net Cash Provided by (Used in) Investing Activities, Continuing Operations |  |  |  |  |  |  |  |  | 997,900,000 | 258,600,000 | 160,400,000
Net cash provided from investing activities — discontinued operations |  |  |  |  |  |  |  |  | 0 | 0 | (13,900,000)
Net cash provided from investing activities |  |  |  |  |  |  |  |  | 997,900,000 | 258,600,000 | 146,500,000
Cash flows from financing activities: |  |  |  |  |  |  |  |  |  |  |
Draw down of debt and revolving line of credit |  |  |  |  |  |  |  |  | 350,000,000 | 125,000,000 | 65,000,000
Repayment of debt and revolving line of credit |  |  |  |  |  |  |  |  | (400,000,000) | (75,000,000) | (65,000,000)
Proceeds from issuances of common shares |  |  |  |  |  |  |  |  | 3,700,000 | 0 | 0
Repurchases and retirement of common shares |  |  |  |  |  |  |  |  | (881,300,000) | (268,600,000) | (128,200,000)
Dividends paid on common shares |  |  |  |  |  |  |  |  | (5,400,000) | (6,000,000) | (6,200,000)
Net Cash Provided by (Used in) Financing Activities, Continuing Operations |  |  |  |  |  |  |  |  | (933,000,000) | (224,600,000) | (134,400,000)
Net cash used for financing activities — discontinued operations |  |  |  |  |  |  |  |  | 0 | 0 | 0
Net cash used for financing activities |  |  |  |  |  |  |  |  | (933,000,000) | (225,000,000) | (134,400,000)
Net change in cash during the period - continuing operations |  |  |  |  |  |  |  |  | 2,800,000 | 100,000 | 0
Cash balance at beginning of year |  |  |  | $ 300,000 |  |  |  | $ 200,000 | 300,000 | 200,000 | 200,000
Cash balance at end of year | $ 3,100,000 |  |  |  | $ 300,000 |  |  |  | 3,100,000 | 300,000 | 200,000
Proceeds from Dividends |  |  |  |  |  |  |  |  |  | 15,000,000 | 29,700,000
Interest Paid |  |  |  |  |  |  |  |  | $ (1,200,000) | $ 0 | $ (300,000)

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- Definition Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 26 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3574-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3521-108585 + Details
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- Definition Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3521-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585 + Details
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- Definition Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3521-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585 + Details
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- Definition Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=64863997&loc=d3e1377-109256 + Details
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- Definition Amount of cash (inflow) outflow from investing activities classified as other. + 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 9 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3098-108585 Reference 3: 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=66902209&loc=d3e3095-108585 + 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 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3098-108585 Reference 2: 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=66902209&loc=d3e3095-108585 + 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 Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585 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 + Details
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- Definition Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity. + References Reference 1: 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=66902209&loc=d3e3291-108585 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 + 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=66902209&loc=d3e3213-108585 + Details
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- Definition Dividends received on equity and other investments during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585 + 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 Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 Reference 2: 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=66902209&loc=d3e3255-108585 + Details
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- Definition Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements. + References Reference 1: 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 2: 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=66902209&loc=d3e3255-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(f)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + 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 Value of investments transferred from the entity's investments in noncash transactions. + References Reference 1: 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 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 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 + Details
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- Definition Issuance Of Debt To From Subsidiaries + References No definition available. + Details
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