Significant Transactions	6 Months Ended
Jun. 30, 2015
Significant Transactions [Abstract]
Significant Transactions	Significant Transactions PassportCard On April 2, 2015, White Mountains closed on its 50/50 joint venture with DavidShield Life Insurance Agency (2000) Ltd. (“DavidShield”) for the development, marketing and distribution of PassportCard travel insurance (“PassportCard”), with White Mountains and DavidShield each contributing $21.0 million of assets to the newly formed entity, PPCI Global Ltd. OneTitle On April 22, 2015, White Mountains agreed to provide up to $13.0 million to OneTitle National Guaranty Company, Inc. (“OneTitle”) and will take a minority stake in the company. OneTitle is a licensed New York title insurance underwriter that works directly with attorneys, lenders, developers and homeowners. The transaction will close subject to regulatory approval. Tranzact On October 10, 2014, White Mountains acquired majority ownership of Tranzact, a leading provider of end-to-end, performance-driven customer acquisition solutions to the insurance sector. White Mountains acquired 63.2% of Tranzact for a purchase price of $177.7 million, representing an enterprise value of $281.2 million. Immediately following the closing, Tranzact completed a recapitalization that allowed for the return of $44.2 million in capital to White Mountains. As of the acquisition date, White Mountains recognized total assets acquired related to Tranzact of $332.8 million, including $41.4 million of tangible assets, $145.1 million of goodwill, and $146.3 million of other intangible assets; and total liabilities assumed of $108.7 million at their estimated fair values. MediaAlpha On March 14, 2014, White Mountains acquired 60% of the outstanding Class A common units of MediaAlpha. MediaAlpha is a California-based advertising technology company offering a transparent online exchange and sophisticated analytical tools that facilitate transactions between buyers (advertisers) and sellers (publishers) of insurance media (clicks and calls), including its own media inventory generated by owned and operated websites. Its exchange operates in four verticals: auto, home, health and life. White Mountains paid an initial purchase price of $28.1 million. The purchase price is subject to adjustment equal to 62.5% of the 2015 gross profit in excess of the 2013 gross profit. As of June 30, 2015 and December 31, 2014, White Mountains has recognized a $7.9 million liability for the contingent purchase price adjustment. After adjustment for the estimated contingent purchase price adjustment, White Mountains recognized total assets acquired related to MediaAlpha of $70.1 million, including $18.3 million of goodwill and $38.5 million of other intangible assets, and total liabilities assumed of $10.0 million, reflecting acquisition date fair values. Wobi On February 19, 2014, White Mountains acquired 54% of the outstanding common shares of Wobi for NIS 14.4 million (approximately $4.1 million based upon the foreign exchange spot rate at the date of acquisition). During 2014, in addition to the common shares, White Mountains also purchased NIS 31.5 million (approximately $8.5 million) of newly-issued convertible preferred shares of Wobi. Wobi is the only price comparison/aggregation business in Israel, with an insurance carrier panel that represents 85% of the premiums written in the Israeli insurance market. Wobi sells four insurance lines of business, primarily personal auto, and operates as an agency, charging upfront commissions on all insurance policy sales. Wobi also offers a pension products comparison service for Israeli customers and is paid transaction fees when customers use the service to connect to companies that sell those pension products. As of the acquisition date, White Mountains recognized total assets acquired related to Wobi of $13.4 million, including $5.5 million of goodwill and $2.9 million of other intangible assets; and total liabilities assumed of $0.7 million at their estimated fair values. During the second quarter of 2015, White Mountains increased its ownership interest in Wobi through the purchase of shares from a non-controlling interest shareholder for NIS 35.0 million (approximately $9.1 million) and newly-issued convertible preferred shares for NIS 25.0 million (approximately $6.6 million). As of June 30, 2015, White Mountains’s ownership share was 95.3% on a fully converted basis. On February 23, 2015, Wobi acquired 56.2% of the outstanding share capital of Tnuva Finansit Ltd. (“Cashboard”) for NIS 9.5 million (approximately $2.4 million). The acquisition of Cashboard accelerated Wobi's development of its pension products comparison service. As of the acquisition date, Wobi recognized total assets acquired of $5.5 million, including $0.3 million of goodwill and $2.8 million of other intangible assets; and total liabilities assumed of $1.2 million at their estimated fair values. During the second quarter of 2015, Wobi purchased newly issued common shares of Cashboard for NIS 10.0 million (approximately $2.6 million), which increased its ownership interest in Cashboard to 68.3%. Star & Shield On January 31, 2014, White Mountains acquired certain assets and liabilities of Star & Shield Holdings LLC, including SSRM, the attorney-in-fact for SSIE, for a purchase price of $1.8 million. White Mountains owns $20.0 million of surplus notes issued by SSIE. Principal and interest on the surplus notes are payable to White Mountains only with approval from the Florida Office of Insurance Regulation. SSIE is a Florida-domiciled reciprocal insurance exchange providing private passenger auto insurance to the public safety community and their families. SSIE is a variable interest entity (“VIE”). As a result of SSRM’s role as the attorney-in-fact to SSIE and the investment in SSIE’s surplus notes, White Mountains is required to consolidate SSIE. At June 30, 2015 and December 31, 2014, consolidated amounts included total assets of $13.4 million and $13.5 million and total liabilities of $27.8 million and $25.9 million, respectively of SSIE. The surplus notes purchased by White Mountains and the corresponding liability included in SSIE's liabilities are eliminated in consolidation. For the three months ended June 30, 2015 and 2014, SSIE had pre-tax losses of $0.8 million and $5.2 million that were recorded in net loss attributable to non-controlling interests. For the six months ended June 30, 2015 and 2014, SSIE had pre-tax losses of $1.9 million and $9.7 million that were recorded in net loss attributable to non-controlling interests.

Significant Transactions

PassportCard

On April 2, 2015, White Mountains closed on its 50/50 joint venture with DavidShield Life Insurance Agency (2000) Ltd. (“DavidShield”) for the development, marketing and distribution of PassportCard travel insurance (“PassportCard”), with White Mountains and DavidShield each contributing $21.0 million of assets to the newly formed entity, PPCI Global Ltd.

OneTitle

On April 22, 2015, White Mountains agreed to provide up to $13.0 million to OneTitle National Guaranty Company, Inc. (“OneTitle”) and will take a minority stake in the company. OneTitle is a licensed New York title insurance underwriter that works directly with attorneys, lenders, developers and homeowners. The transaction will close subject to regulatory approval.

Tranzact

On October 10, 2014, White Mountains acquired majority ownership of Tranzact, a leading provider of end-to-end, performance-driven customer acquisition solutions to the insurance sector. White Mountains acquired 63.2% of Tranzact for a purchase price of $177.7 million, representing an enterprise value of $281.2 million. Immediately following the closing, Tranzact completed a recapitalization that allowed for the return of $44.2 million in capital to White Mountains. As of the acquisition date, White Mountains recognized total assets acquired related to Tranzact of $332.8 million, including $41.4 million of tangible assets, $145.1 million of goodwill, and $146.3 million of other intangible assets; and total liabilities assumed of $108.7 million at their estimated fair values.

MediaAlpha

On March 14, 2014, White Mountains acquired 60% of the outstanding Class A common units of MediaAlpha. MediaAlpha is a California-based advertising technology company offering a transparent online exchange and sophisticated analytical tools that facilitate transactions between buyers (advertisers) and sellers (publishers) of insurance media (clicks and calls), including its own media inventory generated by owned and operated websites. Its exchange operates in four verticals: auto, home, health and life. White Mountains paid an initial purchase price of $28.1 million. The purchase price is subject to adjustment equal to 62.5% of the 2015 gross profit in excess of the 2013 gross profit. As of June 30, 2015 and December 31, 2014, White Mountains has recognized a $7.9 million liability for the contingent purchase price adjustment. After adjustment for the estimated contingent purchase price adjustment, White Mountains recognized total assets acquired related to MediaAlpha of $70.1 million, including $18.3 million of goodwill and $38.5 million of other intangible assets, and total liabilities assumed of $10.0 million, reflecting acquisition date fair values.

Wobi

On February 19, 2014, White Mountains acquired 54% of the outstanding common shares of Wobi for NIS 14.4 million (approximately $4.1 million based upon the foreign exchange spot rate at the date of acquisition). During 2014, in addition to the common shares, White Mountains also purchased NIS 31.5 million (approximately $8.5 million) of newly-issued convertible preferred shares of Wobi. Wobi is the only price comparison/aggregation business in Israel, with an insurance carrier panel that represents 85% of the premiums written in the Israeli insurance market. Wobi sells four insurance lines of business, primarily personal auto, and operates as an agency, charging upfront commissions on all insurance policy sales. Wobi also offers a pension products comparison service for Israeli customers and is paid transaction fees when customers use the service to connect to companies that sell those pension products. As of the acquisition date, White Mountains recognized total assets acquired related to Wobi of $13.4 million, including $5.5 million of goodwill and $2.9 million of other intangible assets; and total liabilities assumed of $0.7 million at their estimated fair values. During the second quarter of 2015, White Mountains increased its ownership interest in Wobi through the purchase of shares from a non-controlling interest shareholder for NIS 35.0 million (approximately $9.1 million) and newly-issued convertible preferred shares for NIS 25.0 million (approximately $6.6 million). As of June 30, 2015, White Mountains’s ownership share was 95.3% on a fully converted basis.

On February 23, 2015, Wobi acquired 56.2% of the outstanding share capital of Tnuva Finansit Ltd. (“Cashboard”) for NIS 9.5 million (approximately $2.4 million). The acquisition of Cashboard accelerated Wobi's development of its pension products comparison service. As of the acquisition date, Wobi recognized total assets acquired of $5.5 million, including $0.3 million of goodwill and $2.8 million of other intangible assets; and total liabilities assumed of $1.2 million at their estimated fair values. During the second quarter of 2015, Wobi purchased newly issued common shares of Cashboard for NIS 10.0 million (approximately $2.6 million), which increased its ownership interest in Cashboard to 68.3%.

Star & Shield

On January 31, 2014, White Mountains acquired certain assets and liabilities of Star & Shield Holdings LLC, including SSRM, the attorney-in-fact for SSIE, for a purchase price of $1.8 million.

White Mountains owns $20.0 million of surplus notes issued by SSIE. Principal and interest on the surplus notes are payable to White Mountains only with approval from the Florida Office of Insurance Regulation.

SSIE is a Florida-domiciled reciprocal insurance exchange providing private passenger auto insurance to the public safety community and their families. SSIE is a variable interest entity (“VIE”). As a result of SSRM’s role as the attorney-in-fact to SSIE and the investment in SSIE’s surplus notes, White Mountains is required to consolidate SSIE. At June 30, 2015 and December 31, 2014, consolidated amounts included total assets of $13.4 million and $13.5 million and total liabilities of $27.8 million and $25.9 million, respectively of SSIE. The surplus notes purchased by White Mountains and the corresponding liability included in SSIE's liabilities are eliminated in consolidation. For the three months ended June 30, 2015 and 2014, SSIE had pre-tax losses of $0.8 million and $5.2 million that were recorded in net loss attributable to non-controlling interests. For the six months ended June 30, 2015 and 2014, SSIE had pre-tax losses of $1.9 million and $9.7 million that were recorded in net loss attributable to non-controlling interests.