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SCHEDULE II CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT - Statement of Cash Flows (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |  |
Net income (loss) attributable to White Mountains’s common shareholders | $ 792.8 | $ (275.4) | $ 708.7
Charges (credits) to reconcile net income to net cash from operations: |  |  |
Net realized and unrealized investment (gains) losses | 93.0 | 380.3 | (686.0)
Net change in other assets and liabilities | 90.4 | 11.7 | 34.8
Net cash provided from (used for) operations | 365.0 | 38.6 | (60.6)
Cash flows from investing activities: |  |  |
Net change in short-term investments | (455.1) | 59.8 | 60.9
Cash pre-funded for ILS funds managed by Elementum | (70.0) | 0.0 | 0.0
Purchases of consolidated subsidiaries, net of cash acquired | (67.9) | 10.6 | (9.1)
Net cash provided from (used for) investing activities | 115.5 | (208.3) | 64.6
Cash flows from financing activities: |  |  |
Repurchases and retirement of common shares | (615.8) | (107.5) | (85.2)
Dividends paid on common shares | (3.0) | (3.1) | (3.2)
Net cash provided from (used for) financing activities – continuing operations | (344.9) | 217.6 | 49.0
Net decrease in cash during the year | 107.3 | 63.1 | 13.6
Cash balance at beginning of year | 147.7 | 84.6 | 71.0
Cash balance at end of year | 255.0 | 147.7 | 84.6
Other long-term investments | 1,488.0 | 1,377.8 |
Amortization of restricted share awards | 14.0 | 14.7 | 16.6
Net income (loss) attributable to non-controlling interests | (80.4) | (46.5) | (45.3)
Net change in (receivables) payables to subsidiaries | 3.3 | 6.5 | 4.8
White Mountains Insurance Group Ltd. |  |  |
CONDENSED FINANCIAL INFORMATION OF THE REGISTRANT |  |  |
Net income (loss) attributable to White Mountains’s common shareholders | 792.8 | (275.4) | 708.7
Charges (credits) to reconcile net income to net cash from operations: |  |  |
Net realized and unrealized investment (gains) losses | 5.6 | 0.1 | 10.1
Undistributed earnings from consolidated subsidiaries | (853.8) | 257.4 | (782.0)
Other non-cash reconciling items | (0.4) | 14.1 | 19.0
Accumulated earnings distributed from subsidiary in cash | 7.0 | 0.0 | 0.0
Net change in other assets and liabilities | 17.2 | (5.7) | (2.5)
Net cash provided from (used for) operations | (31.6) | (28.2) | (44.4)
Cash flows from investing activities: |  |  |
Net change in short-term investments | 1,165.6 | 17.7 | (127.4)
Purchases of investment securities | (359.2) | 0.0 | (6.7)
Sales and maturities of investment securities | 15.7 | 0.0 | 189.7
Purchases of investment securities from subsidiaries | (14.0) | (26.4) | 0.0
Sales of investment securities to subsidiaries | 0.0 | 36.4 | 0.0
Cash pre-funded for ILS funds managed by Elementum | (70.0) | 0.0 | 0.0
Net issuance of debt (to) from subsidiaries | (142.0) | 94.0 | (44.5)
Net repayment of debt to (from) subsidiaries | (15.0) | 0.0 | 92.6
Purchases of consolidated subsidiaries, net of cash acquired | 49.3 | 17.0 | 29.1
Proceeds from the sale of Other Operating Businesses, net of cash sold of $0.5 $0.0 and $0.0 | 19.5 | 0.0 | 0.0
Net cash provided from (used for) investing activities | 649.9 | 138.7 | 132.8
Cash flows from financing activities: |  |  |
Repurchases and retirement of common shares | (615.8) | (107.5) | (85.2)
Dividends paid on common shares | (3.0) | (3.1) | (3.2)
Net cash provided from (used for) financing activities – continuing operations | (618.8) | (110.6) | (88.4)
Net decrease in cash during the year | (0.5) | (0.1) | 0.0
Cash balance at beginning of year | 0.6 | 0.7 | 0.7
Cash balance at end of year | 0.1 | 0.6 | 0.7
Investments in consolidated subsidiaries | 3,026.6 | 3,661.3 |
Fixed maturity investments, at fair value | 49.2 | 0.0 |
Other long-term investments | 49.3 | 0.0 |
Short-term investments at carrying value | 105.2 | 6.7 |
Other assets | 75.3 | 3.0 |
Net income (loss) attributable to non-controlling interests | (7.4) | (2.5) | 1.0
Bridge Holdings, Ltd. |  |  |
Cash flows from investing activities: |  |  |
Net issuance of debt (to) from subsidiaries | (69.0) |  |
Net repayment of debt to (from) subsidiaries | 15.0 |  |
Cash flows from financing activities: |  |  |
Carrying value of stock transferred | 3,540.6 |  |
Intercompany note receivable | 76.4 |  |
Investments in consolidated subsidiaries | 2,003.6 |  |
Fixed maturity investments, at fair value | 28.6 |  |
Common equity securities, at fair value | 8.1 |  |
Other long-term investments | 52.2 |  |
Short-term investments at carrying value | 1,358.7 |  |
Other assets | 6.0 |  |
Cash | 7.0 |  |
Distribution received from subsidiaries |  | 12.6 |
Bridge Holdings, Ltd. | White Mountains Insurance Group Ltd. |  |  |
Cash flows from investing activities: |  |  |
Net repayment of debt to (from) subsidiaries |  | 200.0 |
Purchases of consolidated subsidiaries, net of cash acquired |  | 18.0 |
Bridge Holdings, Ltd. | White Mountains Insurance Group Ltd. | Short-term investments |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | 17.9 |
Bridge Holdings, Ltd. | White Mountains Insurance Group Ltd. | Cash |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | 0.1 |
White Mountains Adams, Inc. |  |  |
Cash flows from financing activities: |  |  |
Contribution to subsidiary | 25.0 |  |
White Mountains Adams, Inc. | White Mountains Insurance Group Ltd. |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | (42.7) |
White Mountains Adams, Inc. | White Mountains Insurance Group Ltd. | Short-term investments |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | (37.1) |
White Mountains Adams, Inc. | White Mountains Insurance Group Ltd. | Cash |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | (5.6) |
HG Global |  |  |
Cash flows from investing activities: |  |  |
Net issuance of debt (to) from subsidiaries | (6.0) |  |
Cash flows from financing activities: |  |  |
Distribution received from subsidiaries | 116.3 | 22.3 |
White Mountains Investments Bermuda |  |  |
Cash flows from investing activities: |  |  |
Net issuance of debt (to) from subsidiaries | (205.0) |  |
Cash flows from financing activities: |  |  |
Contribution to subsidiary | 51.0 |  |
White Mountains Investments Bermuda | White Mountains Insurance Group Ltd. |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | (19.7) |
White Mountains Investments Bermuda | White Mountains Insurance Group Ltd. | Short-term investments |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | 19.1 |
White Mountains Investments Bermuda | White Mountains Insurance Group Ltd. | Cash |  |  |
Cash flows from investing activities: |  |  |
Purchases of consolidated subsidiaries, net of cash acquired |  | 0.6 |
Group Ark Insurance Limited |  |  |
Cash flows from financing activities: |  |  |
Distribution received from subsidiaries | 7.7 |  |
PSC Holdings, Ltd |  |  |
Cash flows from financing activities: |  |  |
Distribution received from subsidiaries | 1.3 | 6.8 |
Non-cash reconciling item | Bridge Holdings, Ltd. |  |  |
Cash flows from financing activities: |  |  |
Transfer to investments |  |  | 169.6
Short-term investments | White Mountains Insurance Group Ltd. |  |  |
Cash flows from financing activities: |  |  |
Transfer to investments |  |  | 169.6
Short-term investments | White Mountains Insurance Group Ltd. | White Mountains Adams, Inc. |  |  |
Cash flows from financing activities: |  |  |
Transfer to investments | 100.0 |  |
WM Lincoln |  |  |
Cash flows from financing activities: |  |  |
Carrying value of stock transferred |  | 212.6 |
Sirius Group |  |  |
Charges (credits) to reconcile net income to net cash from operations: |  |  |
Net (gain) loss from sale of discontinued operations, net of tax - Sirius Group | 0.0 | (18.7) | 2.3
Sirius Group | White Mountains Insurance Group Ltd. |  |  |
Charges (credits) to reconcile net income to net cash from operations: |  |  |
Net (gain) loss from sale of discontinued operations, net of tax - Sirius Group | 0.0 | (18.7) | 2.3
Other Operations |  |  |
Cash flows from investing activities: |  |  |
Proceeds from the sale of Other Operating Businesses, net of cash sold of $0.5 $0.0 and $0.0 | 19.5 | 0.0 | 0.0
Cash sold in subsidiary transaction | $ 0.5 | 0.0 | 0.0
Swedish Tax Authority | Sirius Group |  |  |
Cash flows from financing activities: |  |  |
Loss contingency accrual, period increase (decrease) |  | 18.7 | (2.3)
Swedish Tax Authority | Sirius Group | White Mountains Insurance Group Ltd. |  |  |
Cash flows from financing activities: |  |  |
Loss contingency accrual, period increase (decrease) |  | $ 18.7 | $ (2.3)

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