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Investments in Symetra Investments in Symetra | 9 Months Ended
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Sep. 30, 2017
Investments in and Advances to Affiliates, Schedule of Investments [Abstract] |
Investments in Symetra | Investment in Symetra White Mountains’s investment in Symetra represented an investment in which White Mountains had a significant voting and economic interest but did not control the entity. In August 2015, Symetra announced it had entered into a definitive merger agreement with Sumitomo Life pursuant to which Sumitomo Life would acquire all of the outstanding shares of Symetra. Following the announcement and Symetra shareholders’ November 5, 2015 meeting to approve the transaction, White Mountains relinquished its representation on Symetra’s board of directors. As a result, White Mountains changed its accounting for Symetra common shares from the equity method to fair value as of December 31, 2015. During the fourth quarter of 2015, White Mountains recognized $258.8 million ($241.1 million after tax) of unrealized investment gains through net income, representing the difference between the carrying value of Symetra common shares under the equity method at the date of change and fair value at December 31, 2015. White Mountains also received a special dividend of $0.50 per share as part of the transaction that was paid in the third quarter of 2015. On February 1, 2016, Symetra closed its definitive merger agreement with Sumitomo Life, and White Mountains received proceeds of $658.0 million, or $32.00 per common share. White Mountains recognized $4.7 million in pre-tax net investment gains associated with Symetra in the first quarter of 2016.

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- Definition The entire disclosure for equity method investments and joint ventures. Equity method investments are investments that give the investor the ability to exercise significant influence over the operating and financial policies of an investee. Joint ventures are entities owned and operated by a small group of businesses as a separate and specific business or project for the mutual benefit of the members of the group. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=64825282&loc=d3e32847-111569 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=64825282&loc=d3e32787-111569 + Details
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- References No definition available. + Details
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