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Derivatives (Pre-Tax Operating Results of WM Life Re) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Pre-tax operating results of WM Life Re |  |  |  |  |  |  |  |  |  |  |
Total revenues | $ 678.5 | $ 334.7 | $ 403.6 | $ 391.8 | $ 405.6 | $ 323.2 | $ 393.5 | $ 331.8 | $ 1,808.6 | $ 1,454.1 | $ 1,361.6
General and administrative expenses |  |  |  |  |  |  |  |  | (487.5) | (257.7) | (149.1)
Pre-tax income (loss) | $ 258.1 | $ (94.6) | $ (9.1) | $ 0.5 | $ (65.7) | $ (35.5) | $ 33.6 | $ 38.6 | 154.9 | (29.0) | 158.6
White Mountains Life Re |  |  |  |  |  |  |  |  |  |  |
Pre-tax operating results of WM Life Re |  |  |  |  |  |  |  |  |  |  |
Fees, included in other revenue |  |  |  |  |  |  |  |  | 9.3 | 18.6 | 25.0
Change in Fair Value of Variable Annuity Liability, included in other revenues |  |  |  |  |  |  |  |  | (0.4) | 52.9 | 378.5
Change in fair value of derivatives, included in other revenue |  |  |  |  |  |  |  |  | (8.8) | (72.4) | (402.0)
Foreign exchange, included in other revenue |  |  |  |  |  |  |  |  | (1.3) | (3.2) | (14.5)
Other investment income and (losses) gains |  |  |  |  |  |  |  |  | (0.4) | (1.4) | (7.1)
Total revenues |  |  |  |  |  |  |  |  | (1.6) | (5.5) | (20.1)
Change in fair value of variable annuity death benefit liabilities, included in general and administrative expenses |  |  |  |  |  |  |  |  | 0.0 | 0.6 | 10.2
Death benefit claims paid, included in general and administrative expenses |  |  |  |  |  |  |  |  | (0.1) | (0.1) | (1.9)
General and administrative expenses |  |  |  |  |  |  |  |  | (4.0) | (4.3) | (4.9)
Pre-tax income (loss) |  |  |  |  |  |  |  |  | $ (5.7) | (9.3) | $ (16.7)
Level 3 Inputs | Projected Surrender Assumption [Member] | White Mountains Life Re |  |  |  |  |  |  |  |  |  |  |
Pre-tax operating results of WM Life Re |  |  |  |  |  |  |  |  |  |  |
Change in fair value of derivatives, included in other revenue |  |  |  |  |  |  |  |  |  | $ 0.2 |

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- Definition Income from agency and brokerage operations (includes sales of annuities and supplemental contracts); service charges, commissions, and fees from the sale of insurance and related services; and management fees from separate accounts, deferred annuities, and universal life products. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04.4) -URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(c),(d)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 + Details
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