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Derivatives (Variable Annuity Reinsurance Liabilities and Derivative Instruments (Details) (White Mountains Life Re, USD $) In Millions, unless otherwise specified | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013
Changes in derivative instruments |  |  |  |
Beginning balance |  |  | $ 69.2 |
Realized and unrealized gains (losses) | (26.2) | (63.5) | (32.7) | (245.3)
Ending balance | 74.8 |  | 74.8 |
Change in fair value of variable annuity death benefit liabilities, included in other general and administrative expenses | 0.3 | 1.6 | 0.3 | 7.2
Fair Value |  |  |  |
Changes in derivative instruments |  |  |  |
Beginning balance | 89.6 | 75.8 | 69.2 | 98.3
Purchases | 0 | 23.3 | 0 | 59.4
Realized and unrealized gains (losses) | (26.2) | (63.5) | (32.7) | (245.3)
Transfers in | 0 | 0 | 0 | 0
Sales/settlements | 11.4 | 105.7 | 38.3 | 228.9
Ending balance | 74.8 | 141.3 | 74.8 | 141.3
Level 2 Inputs |  |  |  |
Changes in derivative instruments |  |  |  |
Beginning balance | 25.1 | (42.9) | 4.7 | (20.5)
Purchases | 0 | 0 | 0 | 0
Realized and unrealized gains (losses) | (15.5) | (30.6) | (22.5) | (116.0)
Transfers in | 0 | 0 | 0 | 0
Sales/settlements | 12.7 | 91.7 | 40.1 | 154.7
Ending balance | 22.3 | 18.2 | 22.3 | 18.2
Level 1 Inputs |  |  |  |
Changes in derivative instruments |  |  |  |
Beginning balance | 0.4 | (8.7) | 1.1 | (21.7)
Purchases | 0 | 0 | 0 | 0
Realized and unrealized gains (losses) | (0.1) | (8.7) | (0.3) | (55.9)
Transfers in | 0 | 0 | 0 | 0
Sales/settlements | (1.1) | 14.0 | (1.6) | 74.2
Ending balance | (0.8) | (3.4) | (0.8) | (3.4)
Variable Annuity | Level 3 Inputs |  |  |  |
Changes in derivative instruments |  |  |  |
Beginning balance | (54.1) | (251.6) | (52.8) | (441.5)
Realized and unrealized gains (losses) | 22.3 | 57.5 | 21.0 | 247.4
Transfers in | 0 | 0 | 0 | 0
Sales/settlements | 0 | 0 | 0 | 0
Ending balance | (31.8) | (194.1) | (31.8) | (194.1)
Purchases | 0 |  | 0 |
Derivative [Member] | Level 3 Inputs |  |  |  |
Changes in derivative instruments |  |  |  |
Beginning balance | 64.1 | 127.4 | 63.4 | 140.5
Purchases | 0 | 23.3 | 0 | 59.4
Realized and unrealized gains (losses) | (10.6) | (24.2) | (9.9) | (73.4)
Transfers in | 0 | 0 | 0 | 0
Sales/settlements | (0.2) | 0 | (0.2) | 0
Ending balance | $ 53.3 | $ 126.5 | $ 53.3 | $ 126.5

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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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