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Derivatives (Tables) | 12 Months Ended
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Dec. 31, 2013
Forward contracts |
Derivative [Line Items] |
Fair Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis Table [Text Block] | The following tables summarize the changes in White Mountains’ forward contracts for the year ended December 31, 2013 and 2012:
Millions |  | December 31, 2013 |  | December 31, 2012
Beginning of period |  | $ | (.1 | ) |  | $ | — |
Purchases |  | — |  |  | — |
Realized and unrealized losses |  | (.1 | ) |  | (.3 | )
Sales/settlements |  | .1 |  |  | .2 |
End of period |  | $ | (.1 | ) |  | $ | (.1 | )
Offestting Assets and Liabilities | The following summarizes amounts offset under master netting agreements:
|  | December 31, 2013 |  | December 31, 2012
Millions |  | Gross asset amounts before offsets(1) |  | Gross liability amounts offset under master netting arrangements |  | Net amounts recognized in investments |  | Gross asset amounts before offsets(1) |  | Gross liability amounts offset under master netting arrangements |  | Net amounts recognized in investments
USD |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
EUR |  | — |  |  | (.1 | ) |  | (.1 | ) |  | — |  |  | (.1 | ) |  | (.1 | )
GBP |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total |  | $ | — |  |  | $ | (.1 | ) |  | $ | (.1 | ) |  | $ | — |  |  | $ | (.1 | ) |  | $ | (.1 | )
(1) | Amount equal to fair value of instrument as recognized in investments.
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value | The following summarizes realized and unrealized derivative gains (losses) recognized in net realized and unrealized investment gains and the carrying values, included in other long-term investments, at December 31, 2013 and 2012 by type of currency:
|  | December 31, 2013 |  | December 31, 2012
Millions |  | Gains (Losses) |  | Carrying Value |  | Gains (Losses) |  | Carrying Value
USD |  | $ | (.2 | ) |  | $ | — |  |  | $ | (.2 | ) |  | $ | — |
SEK |  | — |  |  | — |  |  | — |  |  | — |
EUR |  | .1 |  |  | (.1 | ) |  | (.1 | ) |  | (.1 | )
GBP |  | — |  |  | — |  |  | — |  |  | — |
Total |  | $ | (.1 | ) |  | $ | (.1 | ) |  | $ | (.3 | ) |  | $ | (.1 | )
Schedule of Derivative Instruments [Table Text Block] | The following table summarizes the notional amounts and the uncollateralized balances associated with forward currency contracts by counterparty:
|  | December 31, 2013 |  | December 31, 2012
Millions |  | Notional Amount |  | Carrying Value |  | Standard & Poor's Rating(1) |  | Notional Amount |  | Carrying Value
Barclays Bank Plc |  | $ | 5.8 |  |  | $ | — |  |  | A |  | $ | 7.7 |  |  | $ | (.1 | )
Deutsche Bank |  | 7.7 |  |  | — |  |  | A |  | 11.1 |  |  | — |
Goldman Sachs |  | 2.1 |  |  | — |  |  | A- |  | .4 |  |  | — |
HSBC |  | 3.3 |  |  | (.1 | ) |  | AA- |  | 10.1 |  |  | — |
JP Morgan |  | 1.3 |  |  | — |  |  | A+ |  | 1.9 |  |  | — |
Royal Bank of Canada |  | .2 |  |  | — |  |  | AA- |  | — |  |  | — |
Total |  | $ | 20.4 |  |  | $ | (.1 | ) |  |  |  | $ | 31.2 |  |  | $ | (.1 | )
(1) | Standard & Poor’s (“S&P”) ratings as detailed above are: “AA-” (Very Strong, which is the sixth highest of twenty-one creditworthiness ratings), “A+” (Strong, which is the seventh highest of twenty-one creditworthiness ratings) and “A” (Strong, which is the eighth highest of twenty-one creditworthiness ratings).
Variable Annuity Reinsurance |
Derivative [Line Items] |
Pre-tax operating results | The following table summarizes the pre-tax operating results of WM Life Re for the years ended December 31, 2013, 2012 and 2011:
|  | Year Ended December 31,
Millions |  | 2013 |  | 2012 |  | 2011
Fees, included in other revenue |  | $ | 25.0 |  |  | $ | 31.8 |  |  | $ | 32.5 |
Change in fair value of variable annuity liability, included in other revenue |  | 378.5 |  |  | 312.8 |  |  | (156.5 | )
Change in fair value of derivatives, included in other revenue |  | (402.0 | ) |  | (339.0 | ) |  | 92.9 |
Foreign exchange, included in other revenue |  | (14.5 | ) |  | (30.3 | ) |  | 15.1 |
Other investment income and (losses) gains |  | (7.1 | ) |  | 2.5 |  |  | (.9 | )
Total revenues |  | (20.1 | ) |  | (22.2 | ) |  | (16.9 | )
Change in fair value of variable annuity death benefit liabilities, included in general and administrative expenses |  | 10.2 |  |  | 14.2 |  |  | (1.8 | )
Death benefit claims paid, included in general and administrative expenses |  | (1.9 | ) |  | (5.7 | ) |  | (3.8 | )
General and administrative expenses |  | (4.9 | ) |  | (5.2 | ) |  | (4.7 | )
Pre-tax loss |  | $ | (16.7 | ) |  | $ | (18.9 | ) |  | $ | (27.2 | )
Fair Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis Table [Text Block] | The following table summarizes the changes in White Mountains’ variable annuity reinsurance liabilities and derivative instruments for the year ended December 31, 2013, 2012 and 2011:
|  | Variable Annuity (Liabilities) |  | Derivative Instruments
Millions |  | Level 3 |  | Level 3(1) |  | Level 2(1)(2) |  | Level 1(3) |  | Total(4)
Balance at January 1, 2013 |  | $ | (441.5 | ) |  | $ | 140.5 |  |  | $ | (20.5 | ) |  | $ | (21.7 | ) |  | $ | 98.3 |
Purchases |  | — |  |  | 59.4 |  |  | — |  |  | — |  |  | 59.4 |
Realized and unrealized gains (losses) |  | 388.7 |  | (5) | (136.5 | ) |  | (196.1 | ) |  | (69.4 | ) |  | (402.0 | )
Transfers in (out) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Sales/settlements |  | — |  |  | — |  |  | 221.3 |  |  | 92.2 |  |  | 313.5 |
Balance at December 31, 2013 |  | $ | (52.8 | ) |  | $ | 63.4 |  |  | $ | 4.7 |  |  | $ | 1.1 |  |  | $ | 69.2 |
|  | Variable Annuity (Liabilities) |  | Derivative Instruments
Millions |  | Level 3 |  | Level 3(1) |  | Level 2(1)(2) |  | Level 1(3) |  | Total(4)
Balance at January 1, 2012 |  | $ | (768.5 | ) |  | $ | 247.1 |  |  | $ | 39.2 |  |  | $ | 4.1 |  |  | $ | 290.4 |
Purchases |  | — |  |  | 6.1 |  |  | — |  |  | — |  |  | 6.1 |
Realized and unrealized (losses) gains |  | 327.0 |  | (5) | (84.0 | ) |  | (186.9 | ) |  | (68.1 | ) |  | (339.0 | )
Transfers in (out) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Sales/settlements |  | — |  |  | (28.7 | ) |  | 127.2 |  |  | 42.3 |  |  | 140.8 |
Balance at December 31, 2012 |  | $ | (441.5 | ) |  | $ | 140.5 |  |  | $ | (20.5 | ) |  | $ | (21.7 | ) |  | $ | 98.3 |
|  | Variable Annuity (Liabilities) |  | Derivative Instruments
Millions |  | Level 3 |  | Level 3(1) |  | Level 2(1)(2) |  | Level 1(3) |  | Total(4)
Balance at January 1, 2011 |  | $ | (610.2 | ) |  | $ | 275.3 |  |  | $ | 72.2 |  |  | $ | — |  |  | $ | 347.5 |
Purchases |  | — |  |  | 5.0 |  |  | — |  |  | — |  |  | 5.0 |
Realized and unrealized (losses) gains |  | (158.3 | ) | (5) | 14.5 |  |  | 67.7 |  |  | 10.7 |  |  | 92.9 |
Transfers in (out) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Sales/settlements |  | — |  |  | (47.7 | ) |  | (100.7 | ) |  | (6.6 | ) |  | (155.0 | )
Balance at December 31, 2011 |  | $ | (768.5 | ) |  | $ | 247.1 |  |  | $ | 39.2 |  |  | $ | 4.1 |  |  | $ | 290.4 |
(1) | Consists of over-the-counter instruments.
(2) | Consists of interest rate swaps, total return swaps, foreign currency forward contracts, and bond forwards. Fair value measurement based upon bid/ask pricing quotes for similar instruments that are actively traded, where available. Swaps for which an active market does not exist have been priced using observable inputs including the swap curve and the underlying bond index.
(3) | Consists of exchange traded equity index, foreign currency and interest rate futures. Fair value measurements based upon quoted prices for identical instruments that are actively traded.
(4) | In addition to derivative instruments, WM Life Re held cash, short-term and fixed maturity investments of $81.3, $393.6 and $485.3 at December 31, 2013, 2012 and 2011 posted as collateral to its reinsurance counterparties.
(5) | Includes $10.2, $14.2, $(1.8) for December 31, 2013, 2012 and 2011 related to the change in the fair value of variable annuity death benefit liabilities, which are included in general and administrative expenses.
Schedule of collateral [Table Text Block] | In addition, WM Life Re held cash and short-term investments posted as collateral to its variable annuity reinsurance and derivatives counterparties. The total collateral includes the following:
|  | December 31,
Millions |  | 2013 |  | 2012
Cash |  | $ | 56.1 |  |  | $ | 249.8 |
Short-term investments |  | 2.0 |  |  | 5.1 |
Fixed maturity investments |  | 23.2 |  |  | 138.7 |
Total |  | $ | 81.3 |  |  | $ | 393.6 |
Schedule of significant unobservable inputs associated with the fair value estimates for variable annuity reinsurance liabilities and derivative instruments | The following summarizes quantitative information about significant unobservable inputs associated with the fair value estimates for variable annuity reinsurance liabilities and derivative instruments that have been classified as Level 3 measurements:
($ in Millions) |  | December 31, 2013
Description |  | Fair Value |  | Valuation Technique(s) |  | Unobservable Input |  | Range |  | Weighted Average
Variable annuity benefit guarantee liabilities |  | $ | 52.8 |  |  | Discounted cash flows |  | Surrenders |  |  |  |  |  |
|  |  |  | 0-1 year |  | 0.3 | % | - | 30.0% |  | 21.0 | %
|  |  |  | 1-2 years |  | 0.2 | % | - | 32.0% |  | 15.8 | %
|  |  |  | 2-3 years |  | 0.1 | % | - | 14.0% |  | 6.2 | %
|  |  |  |  | Mortality |  | 0.0 | % | - | 5.3% |  | 1.0 | %
|  |  |  |  | Foreign exchange volatilities |  |  |  |  |  |
|  |  |  | 0-1 year |  | 11.6 | % | - | 14.0% |  | 12.5 | %
|  |  |  | 1-2 years |  | 12.9 | % | - | 15.0% |  | 13.7 | %
|  |  |  | 2-3 years |  | 13.5 | % | - | 16.3% |  | 14.3 | %
|  |  |  | Index volatilities |  |  |  |  |  |
|  |  |  | 0-1 year |  | 16.4 | % | - | 19.5% |  | 17.9 | %
|  |  |  | 1-2 years |  | 17.6 | % | - | 20.1% |  | 19.4 | %
|  |  |  |  | 2-3 years |  | 18.9 | % | - | 21.9% |  | 21.9 | %
Foreign Exchange Options |  | $ | 32.6 |  |  | Counterparty valuations, adjusted for unwind quote discount |  | Adjustment to counterparty valuations |  | (1.2 | )% | - | 8.0% |  | 2.4 | %
Equity Index Options |  | $ | 30.8 |  |  | Counterparty valuations, adjusted for unwind quote discount |  | Adjustment to counterparty valuations |  | 0.5% | - | 9.7% |  | 3.4 | %
Offestting Assets and Liabilities | The following summarizes amounts offset under master netting agreements:
|  | December 31, 2013 |  | December 31, 2012
Millions |  | Gross asset amounts before offsets(1) |  | Gross liability amounts offset under master netting arrangements |  | Net amounts recognized in Other Assets |  | Gross asset amounts before offsets(1) |  | Gross liability amounts offset under master netting arrangements |  | Net amounts recognized in Other Assets
Interest rate contracts |  |  |  |  |  |  |  |  |  |  |  |
OTC |  | $ | 2.4 |  |  | $ | (11.7 | ) |  | $ | (9.3 | ) |  | $ | 52.6 |  |  | $ | (26.9 | ) |  | $ | 25.7 |
Exchange traded |  | 1.0 |  |  | (1.6 | ) |  | (.6 | ) |  | 1.6 |  |  | (.2 | ) |  | 1.4 |
Foreign exchange contracts |  |  |  |  |  |  |  |  |  |  |  |
OTC |  | 67.8 |  |  | (12.0 | ) |  | 55.8 |  |  | 87.8 |  |  | (34.4 | ) |  | 53.4 |
Exchange traded |  | 2.3 |  |  | — |  |  | 2.3 |  |  | .8 |  |  | (1.4 | ) |  | (.6 | )
Equity contracts |  |  |  |  |  |  |  |  |  |  |  |
OTC |  | 30.7 |  |  | (9.2 | ) |  | 21.5 |  |  | 63.6 |  |  | (22.9 | ) |  | 40.7 |
Exchange traded |  | 1.8 |  |  | (2.3 | ) |  | (.5 | ) |  | .1 |  |  | (22.4 | ) |  | (22.3 | )
Total(2) |  | $ | 106.0 |  |  | $ | (36.8 | ) |  | $ | 69.2 |  |  | $ | 206.5 |  |  | $ | (108.2 | ) |  | $ | 98.3 |
(1) Amount equal to fair value of instrument as recognized in other assets. (2) All derivative instruments held by WM Life Re are subject to master netting arrangements.
Offsetting Assets | The following summarizes the value, collateral held or provided by WM Life Re and net exposure to credit losses on OTC and exchange traded derivative instruments by counterparty recorded within other assets:
|  | December 31, 2013
Millions |  | Net amount of assets reflected in Balance Sheet |  | Collateral provided to counterparty - Cash |  | Collateral provided to counter-party - Financial Instruments |  | Net amount of exposure after effect of collateral provided |  | Excess collateral provided to counter-party- Cash |  | Excess collateral provided - Financial Instruments |  | Counter-party collateral held by WM Life Re - Cash |  | Net amount of exposure to counter-party |  | Standard & Poor's Rating(1)
JP Morgan |  | $ | 9.1 |  |  | $ | — |  |  | $ | — |  |  | $ | 9.1 |  |  | $ | 22.0 |  |  | $ | — |  |  | $ | — |  |  | $ | 31.1 |  |  | A | +
Bank of America |  | 27.2 |  |  | — |  |  | — |  |  | 27.2 |  |  | — |  |  | — |  |  | — |  |  | 27.2 |  |  | A |
Nomura |  | (.4 | ) |  | — |  |  | .4 |  |  | — |  |  | — |  |  | 22.8 |  |  | .8 |  |  | 22.0 |  |  | BBB | +
Citigroup - OTC |  | 19.4 |  |  | — |  |  | — |  |  | 19.4 |  |  | 2.3 |  |  | — |  |  | — |  |  | 21.7 |  |  | A |
Citigroup - Exchange Traded |  | 1.2 |  |  | — |  |  | — |  |  | 1.2 |  |  | 19.8 |  |  | — |  |  | — |  |  | 21.0 |  |  | A |
Royal Bank of Scotland |  | 11.3 |  |  | — |  |  | — |  |  | 11.3 |  |  | — |  |  | — |  |  | — |  |  | 11.3 |  |  | A | -
Barclays |  | 1.4 |  |  | — |  |  | — |  |  | 1.4 |  |  | — |  |  | — |  |  | — |  |  | 1.4 |  |  | A |
Total |  | $ | 69.2 |  |  | $ | — |  |  | $ | .4 |  |  | $ | 69.6 |  |  | $ | 44.1 |  |  | $ | 22.8 |  |  | $ | .8 |  |  | $ | 135.7 |  |  |  |
|  | December 31, 2012
Millions |  | Net amount of assets reflected in Balance Sheet |  | Collateral provided to counter-party - Cash |  | Collateral provided to counter-party - Financial Instruments |  | Net amount of exposure after effect of collateral provided |  | Excess collateral provided to counter-party- Cash |  | Excess collateral provided - Financial Instruments |  | Counter-party collateral held by WM Life Re- Cash |  | Net amount of exposure to counter-party |  | Standard & Poor's Rating(1)
Citigroup - OTC |  | $ | 19.9 |  |  | $ | — |  |  | $ | — |  |  | $ | 19.9 |  |  | $ | 30.8 |  |  | $ | — |  |  | $ | — |  |  | $ | 50.7 |  |  | A |
Bank of America |  | 78.5 |  |  | — |  |  | — |  |  | 78.5 |  |  | — |  |  | — |  |  | 30.6 |  |  | 47.9 |  |  | A |
Royal Bank of Scotland |  | 33.6 |  |  | — |  |  | — |  |  | 33.6 |  |  | — |  |  | — |  |  | — |  |  | 33.6 |  |  | A |
JP Morgan |  | (22.8 | ) |  | 22.8 |  |  | — |  |  | — |  |  | 32.8 |  |  | — |  |  | — |  |  | 32.8 |  |  | A | +
Nomura |  | (.9 | ) |  | .9 |  |  | — |  |  | — |  |  | .8 |  |  | 28.0 |  |  | — |  |  | 28.8 |  |  | BBB | +
Citigroup - Exchange Traded |  | (21.5 | ) |  | 21.5 |  |  | — |  |  | — |  |  | 13.6 |  |  | — |  |  | — |  |  | 13.6 |  |  | A |
Barclays |  | 11.6 |  |  | — |  |  | — |  |  | 11.6 |  |  | — |  |  | — |  |  | — |  |  | 11.6 |  |  | A | +
Goldman Sachs |  | (.1 | ) |  | .1 |  |  | — |  |  | — |  |  | 3.1 |  |  | — |  |  | — |  |  | 3.1 |  |  | A | -
Total |  | $ | 98.3 |  |  | $ | 45.3 |  |  | $ | — |  |  | $ | 143.6 |  |  | $ | 81.1 |  |  | $ | 28.0 |  |  | $ | 30.6 |  |  | $ | 222.1 |  |  |  |
(1) | Standard & Poor’s ratings as detailed above are: “A+” (Strong, which is the fifth highest of twenty-one creditworthiness ratings),“A” (which is the sixth highest of twenty-one creditworthiness ratings), “A-” (which is the seventh highest of twenty-one creditworthiness ratings), and BBB+ (which is the eighth highest of twenty-one creditworthiness ratings).
Realized and unrealized derivative gains (losses) recognized in other revenues and carrying values, by the type of instrument | The following summarizes realized and unrealized gains (losses) recognized in other revenues for the years ended December 31, 2013, 2012 and 2011 and the carrying values at December 31, 2013 and 2012 by type of derivative instrument:
|  |  |  |  |  |  |  | Carrying Value
|  | Year Ended December 31, |  | December 31,
Millions |  | 2013 |  | 2012 |  | 2011 |  | 2013 |  | 2012
Fixed income/interest rate |  | $ | (108.7 | ) |  | $ | (149.5 | ) |  | $ | 8.9 |  |  | $ | (9.7 | ) |  | $ | 27.1 |
Foreign exchange |  | (96.7 | ) |  | (102.3 | ) |  | 29.5 |  |  | 58.0 |  |  | 52.8 |
Equity |  | (196.6 | ) |  | (87.2 | ) |  | 54.5 |  |  | 20.9 |  |  | 18.4 |
Total |  | $ | (402.0 | ) |  | $ | (339.0 | ) |  | $ | 92.9 |  |  | $ | 69.2 |  |  | $ | 98.3 |
Interest Rate Cap |
Derivative [Line Items] |
Fair Value of Assets and Liabilities Measured on Recurring and Non-recurring Basis Table | The following table summarizes the change in the fair value of the Interest Rate Cap for the year ended December 31, 2013:
Millions |  | December 31, 2013
Beginning of period |  | $ | — |
Purchases |  | 9.9 |
Net realized and unrealized gains |  | 1.2 |
Sales/settlements |  | — |
End of period |  | $ | 11.1 |
Assets Held under Reinsurance Counterparty Trust Agreement [Table Text Block] | The following table summarizes the Interest Rate Cap collateral balances held by White Mountains and ratings by counterparty:
|  | December 31, 2013
Millions |  | Collateral Balances Held |  | Standard & Poor’s Rating(1)
Barclays Bank Plc |  | $ | 7.5 |  |  | A
Nordea Bank Finland Plc |  | 3.3 |  |  | AA-
Total |  | $ | 10.8 |  |  |
(1) | Standard & Poor’s ratings as detailed above are: “A” (Strong, which is the sixth highest of twenty-one creditworthiness ratings) and “AA-” (Very Strong, which is the fourth highest of twenty-one creditworthiness ratings).

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