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Summary of Significant Accounting Policies | 12 Months Ended
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Dec. 31, 2017
Accounting Policies [Abstract] |
Summary of Significant Accounting Policies | Significant Accounting Policies Basis of Presentation The Company is an exempted Bermuda limited liability company whose principal businesses are conducted through its insurance subsidiaries and other affiliates. The Company’s headquarters is located at 26 Reid Street, Hamilton, Bermuda HM 11, its principal executive office is located at 80 South Main Street, Hanover, New Hampshire 03755-2053 and its registered office is located at Clarendon House, 2 Church Street, Hamilton, Bermuda HM 11. The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the accounts of White Mountains Insurance Group, Ltd. (the “Company” or the “Registrant”), its subsidiaries (collectively with the Company, “White Mountains”) and other entities required to be consolidated under GAAP. Under GAAP, the Company is required to consolidate any entity in which it holds a controlling financial interest. A controlling financial interest is usually in the form of an investment representing the majority of the subsidiary’s voting interests. However, a controlling financial interest may also arise from a financial interest in a variable interest entity (“VIE”) through arrangements that do not involve ownership of voting interests. The Company consolidates a VIE if it determines that it is the primary beneficiary. The primary beneficiary is defined as the entity who holds a variable interest that gives it both the power to direct the VIE’s activities that most significantly impact its economic performance and the obligation to absorb losses of, or the right to receive returns from, the VIE that could potentially be significant to the VIE. See Note 15 — “Variable Interest Entities”. Intercompany transactions have been eliminated in consolidation. Certain amounts in the prior period financial statements have been reclassified to conform to the current presentation. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Reportable Segments White Mountains has determined its reportable segments based on the nature of the of the underlying businesses, the manner in which the Company’s subsidiaries and affiliates are organized and managed and the organization of the financial information provided to the chief operating decision maker to assess performance and make decisions regarding allocation of resources. White Mountains’s reportable segments are HG Global/BAM, MediaAlpha and Other Operations. See Note 13 — “Segment Information”. The HG Global/BAM segment consists of HG Global Ltd. and its wholly-owned subsidiaries (“HG Global”) and the consolidated results of Build America Mutual Assurance Company (“BAM”) (collectively, “HG Global/BAM”). BAM is the first and only mutual municipal bond insurance company in the United States. By insuring the timely payment of principal and interest, BAM provides market access to, and lowers interest expense for, issuers of municipal bonds used to finance essential public purposes such as schools, utilities and transportation facilities. BAM is owned by and operated for the benefit of its members, the municipalities that purchase BAM’s insurance for their debt issuances. HG Global was established to fund the startup of BAM and, through its wholly-owned subsidiary HG Re Ltd. (“HG Re”), to provide up to 15%-of-par, first loss reinsurance protection for policies underwritten by BAM. HG Global, together with its subsidiaries, provided the initial capitalization of BAM through the purchase of $503.0 million of surplus notes issued by BAM (the “BAM Surplus Notes”). As of December 31, 2017 and 2016, White Mountains owned 96.9% of HG Global's preferred equity and 88.4% of its common equity. White Mountains does not have an ownership interest in BAM. However, White Mountains is required to consolidate BAM’s results in its financial statements because BAM is a VIE for which White Mountains is the primary beneficiary. BAM’s results are attributed to non-controlling interests. The MediaAlpha segment consists of QL Holdings LLC and its wholly-owned subsidiary QuoteLab, LLC (collectively “MediaAlpha”). MediaAlpha is a leading marketing technology company that develops technology that enables the programmatic buying and selling of vertical-specific, performance-based media between advertisers (buyers of advertising inventory) and publishers (sellers of advertising inventory) through cost-per-click, cost-per-call and cost-per-lead pricing models. MediaAlpha’s media buying platform enables advertisers to create and automate data-driven bidding strategies designed to improve the efficiency and enhance overall performance of their marketing campaigns that target high-intent consumers at the time and place they are ready to purchase. MediaAlpha’s publisher platform is used by publishers to sell their vertical-specific, performance-based media to advertisers through transparent, programmatic, auction-based marketplaces. MediaAlpha works with 400 advertisers and 300 publishers across a number of insurance (auto, motorcycle, home, renter, health and life) and non-insurance (travel, education, personal finance and home services) verticals. White Mountains’s Other Operations segment consists of the Company, its wholly-owned subsidiary, White Mountains Capital, Inc. (“WM Capital”), its wholly-owned investment management subsidiary, White Mountains Advisors LLC (“WM Advisors”), and its other intermediate holding companies, as well as certain consolidated and unconsolidated private capital and other investments. The consolidated private capital investments include Wobi Insurance Agency Ltd. (“Wobi”) and Removal Stars Ltd. (“Buzzmove”). During 2017, White Mountains revised certain of its previously issued financial statements for amounts relating to Wobi. See Note 20 — “Financial Statement Revisions”. White Mountains’s Other Operations segment also included its variable annuity reinsurance business, White Mountains Life Reinsurance (Bermuda) Ltd. (“Life Re Bermuda”), which completed its runoff with all of its contracts fully matured on June 30, 2016 and was liquidated in the third quarter of 2017, and its U.S.-based service provider, White Mountains Financial Services LLC, which was liquidated in the second quarter of 2017 (collectively, “WM Life Re”). Discontinued Operations and Assets and Liabilities Held for Sale On September 28, 2017, Intact Financial Corporation completed its previously announced acquisition of OneBeacon Insurance Group, Ltd. (“OneBeacon”) in an all-cash transaction for $18.10 per share (the “OneBeacon Transaction”). On July 21, 2016, White Mountains completed its sale of Tranzact Holdings, LLC (“Tranzact”) to an affiliate of Clayton, Dubilier & Rice, LLC. On April 18, 2016, White Mountains completed its sale of Sirius International Insurance Group, Ltd. (“Sirius Group”) to CM International Pte. Ltd. and CM Bermuda Limited (collectively “CMI”), the Singapore-based investment arm of China Minsheng Investment Corp., Ltd. White Mountains has presented the results of OneBeacon, Tranzact and Sirius Group as discontinued operations in the statement of operations and comprehensive income and their assets and liabilities as held for sale in the balance sheet for all periods prior to the completion of each transaction. On March 7, 2017, White Mountains completed the sale of Star & Shield Services LLC, Star & Shield Risk Management LLC, and Star & Shield Claims Services LLC (collectively “Star & Shield”) and its investment in Star & Shield Insurance Exchange (“SSIE”) surplus notes to K2 Insurance Services, LLC. White Mountains was required to consolidate SSIE in its GAAP financial statements until White Mountains completed the sale. White Mountains has presented Star & Shield’s and SSIE’s assets and liabilities as held for sale as of December 31, 2016. See Note 19 — “Held for Sale and Discontinued Operations”. As of December 31, 2017, White Mountains has classified its Guilford, Connecticut property, which consists of an office building and adjacent land, as held for sale. The property has been measured at its estimated fair value net of costs of disposal, of $3.3 million. The fair value reflects a write-down of $3.7 million, which has been recorded within other expenses. Significant Accounting Policies Cash Cash includes amounts on hand and demand deposits with banks and other financial institutions. Amounts presented in the statement of cash flows are shown net of balances acquired and sold in the purchase or sale of the Company’s consolidated subsidiaries and exclude changes in amounts of restricted cash. See Note 7 — “Derivatives”. Short-Term Investments Short-term investments consist of interest bearing money market funds, certificates of deposit, time deposits and other securities, which at the time of purchase, mature or become available for use within one year. Short-term investments are carried at amortized or accreted cost, which approximated fair value as of December 31, 2017 and 2016. Investment Securities As of December 31, 2017, White Mountains’s invested assets consisted of securities and other investments held for general investment purposes. White Mountains’s portfolio of fixed maturity investments, common equity securities and other long-term investments held for general investment purposes are classified as trading securities and are reported at fair value as of the balance sheet date. Changes in net unrealized investment gains (losses) are reported pre-tax in revenues. Realized investment gains (losses) are accounted for using the specific identification method and are reported pre-tax in revenues. Premiums and discounts on all fixed maturity investments are amortized and accreted to income over the anticipated life of the investment. White Mountains’s invested assets that are measured at fair value include fixed maturity investments, common equity securities and other long-term investments, including interests in hedge funds, private equity funds, non-controlling interests in private capital investments and foreign currency forward contracts. In determining its estimates of fair value, White Mountains uses a variety of valuation approaches and inputs. Whenever possible, White Mountains estimates fair value using valuation methods that maximize the use of quoted prices and other observable inputs. Fair value measurements are categorized into a hierarchy that distinguishes between inputs based on market data from independent sources (“observable inputs”) and a reporting entity’s internal assumptions based upon the best information available when external market data is limited or unavailable (“unobservable inputs”). Quoted prices in active markets for identical assets or liabilities have the highest priority (“Level 1”), followed by observable inputs other than quoted prices, including prices for similar but not identical assets or liabilities (“Level 2”) and unobservable inputs, including the reporting entity’s estimates of the assumptions that market participants would use, having the lowest priority (“Level 3”). As of December 31, 2017 and 2016, White Mountains used quoted market prices or other observable inputs to determine fair value for approximately 94% of the investment portfolio. Investments valued using Level 1 inputs include fixed maturity investments, primarily investments in U.S. Treasuries, short-term investments, which include U.S. Treasury Bills and common equity securities. Investments valued using Level 2 inputs include fixed maturity investments, which have been disaggregated into classes, including debt securities issued by corporations, mortgage and asset-backed securities, municipal obligations, and foreign government, agency and provincial obligations. Investments valued using Level 2 inputs also include certain passive exchange traded funds (“ETFs”) that track U.S. stock indices such as the S&P 500 but are traded on foreign exchanges, which management values using the fund manager’s published NAV to account for the difference in market close times. Fair value estimates for investments that trade infrequently and have few or no observable market prices are classified as Level 3 measurements. Investments valued using Level 3 fair value estimates are based upon unobservable inputs and include investments in certain fixed maturity investments, common equity securities and other long-term investments where quoted market prices are unavailable or are not considered reasonable. Transfers between levels are based on investments held as of the beginning of the period. White Mountains uses brokers and outside pricing services to assist in determining fair values. For investments in active markets, White Mountains uses the quoted market prices provided by outside pricing services to determine fair value. The outside pricing services White Mountains uses have indicated that they will only provide prices where observable inputs are available. In circumstances where quoted market prices are unavailable or are not considered reasonable, White Mountains estimates the fair value using industry standard pricing methodologies and observable inputs such as benchmark yields, reported trades, broker-dealer quotes, issuer spreads, benchmark securities, bids, offers, credit ratings, prepayment speeds, reference data including research publications and other relevant inputs. Given that many fixed maturity investments do not trade on a daily basis, the outside pricing services evaluate a wide range of fixed maturity investments by regularly drawing parallels from recent trades and quotes of comparable securities with similar features. The characteristics used to identify comparable fixed maturity investments vary by asset type and take into account market convention. White Mountains’s process to assess the reasonableness of the market prices obtained from the outside pricing sources covers substantially all of its fixed maturity investments and includes, but is not limited to, the evaluation of pricing methodologies and a review of the pricing services’ quality control procedures on at least an annual basis, a comparison of its invested asset prices obtained from alternate independent pricing vendors on at least a semi-annual basis, monthly analytical reviews of certain prices and a review of the underlying assumptions utilized by the pricing services for select measurements on an ad hoc basis throughout the year. White Mountains also performs back-testing of selected sales activity to determine whether there are any significant differences between the market price used to value the security prior to sale and the actual sale price on an ad-hoc basis throughout the year. Prices provided by the pricing services that vary by more than 5% and $1.0 million from the expected price based on these assessment procedures are considered outliers. Also considered outliers are prices that have not changed from period to period and prices that have trended unusually compared to market conditions. In circumstances where the results of White Mountains’s review process does not appear to support the market price provided by the pricing services, White Mountains challenges the vendor provided price. If White Mountains cannot gain satisfactory evidence to support the challenged price, it relies upon its own pricing methodologies to estimate the fair value of the security in question. The valuation process described above is generally applicable to all of White Mountains’s fixed maturity investments. The techniques and inputs specific to asset classes within White Mountains’s fixed maturity investments for Level 2 securities that use observable inputs are as follows: Debt Securities Issued by Corporations: The fair value of debt securities issued by corporations is determined from a pricing evaluation technique that uses information from market sources and integrates relative credit information, observed market movements, and sector news. Key inputs include benchmark yields, reported trades, broker-dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including sector, coupon, credit quality ratings, duration, credit enhancements, early redemption features and market research publications. Mortgage and Asset-Backed Securities: The fair value of mortgage and asset-backed securities is determined from a pricing evaluation technique that uses information from market sources and leveraging similar securities. Key inputs include benchmark yields, reported trades, underlying tranche cash flow data, collateral performance, plus new issue data, as well as broker-dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including issuer, vintage, loan type, collateral attributes, prepayment speeds, default rates, recovery rates, cash flow stress testing, credit quality ratings and market research publications. Municipal Obligations: The fair value of municipal obligations is determined from a pricing evaluation technique that uses information from market makers, brokers-dealers, buy-side firms, and analysts along with general market information. Key inputs include benchmark yields, reported trades, issuer financial statements, material event notices and new issue data, as well as broker-dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers, and reference data including type, coupon, credit quality ratings, duration, credit enhancements, geographic location and market research publications. Foreign Government, Agency and Provincial Obligations: The fair value of foreign government, agency and provincial obligations is determined from a pricing evaluation technique that uses feeds from data sources in each respective country, including active market makers and inter-dealer brokers. Key inputs include benchmark yields, reported trades, broker-dealer quotes, two-sided markets, benchmark securities, bids, offers, local exchange prices, foreign exchange rates and reference data including coupon, credit quality ratings, duration and market research publications. Level 3 valuations are generated from techniques that use assumptions not observable in the market. These unobservable assumptions reflect White Mountains’s assumptions that market participants would use in valuing the investment. Generally, certain securities may start out as Level 3 when they are originally issued but as observable inputs become available in the market, they may be reclassified to Level 2. Other Long-Term Investments Other long-term investments consist primarily of hedge funds, private equity funds, non-controlling interests in private capital investments and foreign currency forward contracts. See Note 3 — “Investment Securities”. White Mountains has taken the fair value option for most of its other long-term investments. For the investments for which White Mountains has taken the fair value option, changes in fair value are reported in revenues on a pre-tax basis. For those long-term investments for which White Mountains has not made the fair value election, White Mountains accounts for its interests under the equity method. White Mountains employs a number of procedures to assess the reasonableness of the fair value measurements for its other long-term investments, including obtaining and reviewing periodic and audited annual financial statements of hedge funds and private equity funds as well as discussing each fund’s pricing with the fund manager throughout the year. However, since the fund managers do not provide sufficient information to evaluate the pricing methods and inputs for each underlying investment, White Mountains considers the inputs to be unobservable. The fair value of White Mountains’s investments in hedge funds and private equity funds has generally been determined using the fund manager’s NAV. In the event White Mountains believes that the fair value of a hedge fund or private equity fund differs from the NAV reported by the fund manager due to illiquidity or other factors, White Mountains will adjust the reported NAV to more appropriately represent the fair value of its investment in the hedge fund or private equity fund. As of December 31, 2017 and 2016, White Mountains did not adjust the reported NAV of its investments in hedge funds and private equity funds. Derivatives Financial Instruments: White Mountains holds from time to time a variety of derivative financial instruments for risk management purposes. White Mountains recognizes all derivatives as either other assets or other liabilities, aside from the foreign currency forward contracts which are recognized within other long-term investments, measured at fair value, in the consolidated balance sheets. Changes in the fair value of derivative instruments are recognized in current period pre-tax income. From time to time, White Mountains holds warrants that it has received in the restructuring of certain of its common equity securities and fixed maturity investments. White Mountains accounts for its investments in warrants as derivatives. Variable Annuity Reinsurance: In 2016, White Mountains completed the run-off of WM Life Re as all of its contracts matured as of June 30, 2016. WM Life Re entered into agreements to reinsure death and living benefit guarantees associated with certain variable annuities in Japan. The accounting for benefit guarantees differs depending on whether or not the guarantee is classified as a derivative or an insurance liability. The liability for guaranteed minimum death benefits was classified as a derivative and measured at fair value. The liability for guaranteed minimum accumulation benefits was classified as an insurance liability, and was measured using assumptions for interest rates, equity markets, foreign exchange rates and market volatilities at the valuation date, as well as annuitant-related actuarial assumptions, including surrender and mortality rates. WM Life Re entered into derivative contracts that were designed to economically hedge against changes in the fair value of living and death benefit liabilities associated with its variable annuity reinsurance arrangements. All WM Life Re’s derivative financial instruments were recorded as assets or liabilities at fair value on the balance sheet within other assets. These derivative financial instruments did not meet the criteria for hedge accounting treatment, and accordingly, changes in fair value were recognized in the appropriate period as gains or losses in the income statement within other revenues. Receivables Receivables consist primarily of premiums receivable from BAM customers for municipal bond insurance policies and advertising fees receivable from publishers and advertisers of MediaAlpha. Incentive Compensation White Mountains’s Long-Term Incentive Plan (the “WTM Incentive Plan”) provides for grants of various types of share-based and non-share-based incentive awards to key employees of White Mountains. Non-share based awards are recognized over the related service periods based on management’s best estimate of the amounts at which the awards are expected to be paid. Share-based compensation which is typically settled in cash, such as performance shares or performance units, is classified as a liability-type award. The compensation cost for liability-classified awards is measured initially at the grant date fair value and remeasured each reporting period until settlement. The compensation cost for equity-classified awards expected to be settled in shares, such as options and restricted shares, is measured at the original grant date fair value of the award. The compensation cost for all awards is recognized for the vested portion of the awards over the related service periods. See Note 10 — “Employee Share-Based Incentive Compensation”. Goodwill and Other Intangible Assets Goodwill represents the excess of the amount paid to acquire subsidiaries over the fair value of identifiable net assets at the date of acquisition. Other intangible assets consist primarily of trademarks, URL and online names, customer relationships, information technology and insurance licenses. Goodwill is not amortized, but rather is evaluated for impairment on an annual basis, or whenever indications of potential impairment exist. In the absence of any indications of potential impairment, the evaluation of goodwill is performed during the fourth quarter of each year. White Mountains initially evaluates goodwill using a qualitative approach (step zero) to determine whether it is more likely than not that the fair value of goodwill is greater than its carrying value. If the results of the qualitative evaluation indicate that it is more likely than not that the carrying value of goodwill exceeds its fair value, White Mountains performs the two-step quantitative test for impairment. Other intangible assets with finite lives are measured at their acquisition date fair values, are amortized over their economic lives and presented net of accumulated amortization on the balance sheet. Other intangible assets with finite lives are evaluated for impairment at least annually and when events or changes in circumstances indicate that it is more likely than not that the asset is impaired. White Mountains evaluated the recoverability of goodwill and other intangible assets and did not recognize any impairment losses for any of the years ended December 31, 2017, 2016 and 2015. See Note 4 — “Goodwill and Other Intangible Assets”. Municipal Bond Guarantee Insurance All of the contracts issued by BAM are accounted for as insurance contracts under ASC 944-605, Financial Guarantee Insurance Contracts. Premiums are generally received upfront and an unearned premium revenue liability, equal to the amount of the premium received, is established at contract inception. Installment premiums are measured at the present value of contractual premiums, discounted at the risk free rate, which is set at the inception of the insurance contract. Premium revenues are recognized in revenue over the period of the contracts in proportion to the amount of insurance protection provided using a constant rate. The constant rate is calculated based on the relationship between the par outstanding in a given reporting period compared with the sum of each of the par amounts outstanding for all periods. Deferred acquisition costs represent commissions, premium taxes, excise taxes and other costs which are directly attributable to and vary with the production of business. These costs are deferred and amortized to the extent they relate to successful contract acquisitions over the applicable premium recognition period as acquisition expenses. Deferred acquisition costs are limited to the amount expected to be recovered from future earned premiums and anticipated investment income. BAM’s obligation for outstanding contracts consists of the unearned premium reserve and any loss reserves. Loss reserves are recorded only to the extent that the present value of the expected amount of any losses to be paid, net of any expected recoveries, exceeds the associated unearned premium reserve. As of December 31, 2017 and 2016, BAM did not have any loss or LAE reserves. Revenue Recognition White Mountains recognizes advertising and publishing fee revenues based on the contractual amount of the fees, adjusted for any amounts expected to be refunded or uncollectible, when it has satisfied its contractual performance obligations, which is generally at the time each transaction is executed. For transactions where MediaAlpha acts as the principal, such as the Buyer and Open exchanges, revenue amounts are reported gross. For transactions where MediaAlpha acts as an agent facilitating transactions between third parties, revenue amounts are reported at the net fee billed. Agent and commission revenues are measured based on the contractual rates with insurance carriers, net of any amounts expected to be uncollectible and any amounts associated with expected policy cancellations adjustments, and are recognized when contractual performance obligations have been fulfilled. Cost of Sales White Mountains’s cost of sales consists primarily of revenue sharing payments to publisher partners and traffic acquisition costs to top tier search engines. Cost of sales are measured based on contract terms and recognized when the related revenue transactions are executed. Other segment cost of sales consist of salaries and related expenses, professional services and marketing and advertising expenses directly related to sales generation. These expenses are recognized as incurred. Federal and Foreign Income Taxes A number of White Mountains’s subsidiaries file consolidated tax returns in the United States. Income earned or losses generated by companies outside the United States are generally subject to an overall effective tax rate lower than that imposed by the United States. Deferred tax assets and liabilities are recorded when a difference between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts for tax purposes exists, and for other temporary differences. The deferred tax asset or liability is recorded based on tax rates expected to be in effect when the difference reverses. The deferred tax asset is recognized when it is more likely than not that it will be realized. Foreign Currency Exchange The functional currency for White Mountains’s non-U.S. based subsidiaries are measured, in most instances, using functional currencies other than the U.S. dollar. Net foreign exchange gains and losses arising from the translation of functional currencies are generally reported in shareholders’ equity, in accumulated other comprehensive income or loss. White Mountains also invests in securities denominated in foreign currencies. Assets and liabilities recorded in these foreign currencies are translated into U.S. dollars at exchange rates in effect at the balance sheet date, and revenues and expenses are converted using the weighted average exchange rates for the period. As of December 31, 2017 and 2016, White Mountains had unrealized foreign currency translation losses of $1.3 million and $1.4 million recorded in accumulated other comprehensive income on its consolidated balance sheet. Non-controlling Interests Non-controlling interests consist of the ownership interests of non-controlling shareholders in consolidated subsidiaries, and are presented separately on the balance sheet. The portion of comprehensive income attributable to non-controlling interests is presented net of related income taxes in the statement of operations and comprehensive income. See Note 11 — “Common Shareholders’ Equity and Non-controlling Interests”. Recently Adopted Changes in Accounting Principles Stock Compensation Effective January 1, 2017, White Mountains adopted ASU 2016-09, Improvements to Employee Share-Based Payment Accounting (ASC 718) which is intended to simplify certain aspects of the accounting for share-based compensation, including forfeiture assumptions, net settlement of equity awards for withholding taxes and accounting for excess tax benefits. The new guidance provides an accounting policy election to account for forfeitures by either applying an assumption, as required under existing guidance, or by recognizing forfeitures when they actually occur. The new ASU also permits net settlement of equity awards for withholding taxes up to the maximum statutory rate and requires such amounts to be classified as financing activities in the statement of cash flows. In addition, the new guidance changes the accounting for excess tax benefits and deficiencies by requiring recognition in the income statement, with treatment of the tax effects as discrete items in determining a reporting entity’s effective rate in the period in which exercise or vesting of awards occurs. The new guidance became effective on January 1, 2017 for White Mountains and upon adoption changes were recognized in the statement of cash flows with no other significant effect on the rest of the financial statements. Business Combinations - Measurement Period Adjustments Effective January 1, 2016, White Mountains adopted ASU 2015-16, Simplifying the Accounting for Measurement-Period Adjustments, which requires adjustments to provisional amounts recorded in connection with a business combination that are identified during the measurement period to be recorded in the reporting period in which the adjustment amounts are determined, rather than as retroactive adjustments to prior periods. White Mountains has not recognized any adjustments to estimated purchase accounting amounts for the year to date period ended December 31, 2016 and accordingly, there was no effect to White Mountains’s financial statements upon adoption. Fair Value Measurements On January 1, 2016, White Mountains adopted ASU 2015-07, Fair Value Measurement - Disclosures for Investments in Certain Entities that Calculate Net Asset Value per Share (or Its Equivalent) (ASC 820), which eliminates the requirement to disclose the fair value hierarchy level for investments for which fair value is measured at net asset value (“NAV”) using the practical expedient in ASC 820. White Mountains measures the fair value of its investments in hedge funds and private equity funds using this practical expedient. Upon adoption, these fair value measurements are no longer classified within the fair value hierarchy. Amendments to Consolidation Analysis On January 1, 2016, White Mountains adopted ASU 2015-02, Amendments to the Consolidation Analysis (ASC 810) which amends the guidance for determining whether an entity is a VIE. ASU 2015-02 eliminates the separate consolidation guidance for limited partnerships and, with it, the presumption that a general partner should consolidate a limited partnership. In addition, ASU 2015-02 changes the guidance for determining if fee arrangements qualify as variable interests and the effect fee arrangements have on the determination of the primary beneficiary. Adoption of ASU 2015-02 did not affect the consolidation analysis for any of White Mountains’s investments. Share-Based Compensation Awards On January 1, 2016, White Mountains adopted ASU 2014-12, Share-Based Payments When the Terms of an Award Provide That a Performance Target Could Be Achieved after the Requisite Service Period (ASC 718). The new guidance requires that a performance target that affects vesting and that can be achieved after the requisite service period be treated as a performance condition. Compensation cost is to be recognized in the period when it becomes probable the performance target will be achieved in an amount equal to the compensation cost attributable to the periods for which service has been rendered. Adoption did not have a significant effect on White Mountains’s financial statements. Recently Issued Accounting Pronouncements Revenue Recognition Effective January 1, 2018, White Mountains plans to adopt ASU 2014-09, Revenue from Contracts with Customers (ASC 606), which modifies the guidance for revenue recognition. Under the new guidance, revenue is recognized at an amount that reflects the consideration to which an entity expects to be entitled once it fulfills its performance obligations under the terms of its contract with the customer. The new guidance does not apply to revenue from insurance contracts, investment income or investments gains and losses. The new guidance is applicable to some of White Mountains’s revenue streams, including agent commissions and other non-insurance revenues. White Mountains does not expect adoption to have any significant effect on its financial statements. Stock Compensation In May 2017, the FASB issued ASU 2017-09, Stock Compensation: Scope of Modification Accounting (ASC 718), which narrows the scope of transactions subject to modification accounting to changes in terms of an award that result in a change in the award’s fair value, vesting conditions or classification. The new guidance becomes effective for fiscal years beginning after December 15, 2017. White Mountains does not expect adoption to have any effect on its financial statements. Premium Amortization on Callable Debt Securities In March 2017, the FASB issued ASU 2017-08, Premium Amortization on Purchased Callable Debt Securities (ASC 310-20), which changes the amortization period for certain purchased callable debt securities. Under the new guidance, for investments in callable debt securities held at a premium, the premium will be amortized over the period to the earliest call date. The new guidance does not change the amortization period for callable debt securities held at a discount. The new guidance is effective for annual periods beginning after December 15, 2018. White Mountains does not expect adoption to have any effect on its financial statements. Definition of a Business In January 2017, the FASB issued ASU 2017-07, Business Combinations: Clarifying the Definition of a Business (ASC 805), which clarifies the definition of a business and affects the determination of whether acquisitions or disposals are accounted for as assets or as a business. Under the new guidance, when substantially all of the fair value of the assets is concentrated in a single identifiable asset or a group of similar identifiable assets, it is not a business. The new guidance is effective for annual and interim periods after December 15, 2017. White Mountains does not expect adoption to have any effect on its financial statements. Goodwill In January 2017, the FASB issue ASU 2017-04, Simplifying the Test for Goodwill Impairment (ASC 350), which changes the guidance on goodwill impairment testing. Under the new guidance, the qualitative assessment of the recoverability of goodwill remains the same. However, the second step required under the existing guidance has been eliminated. Goodwill is considered impaired if the carrying value exceeds the estimated fair value. The new guidance is effective for fiscal years beginning after December 15, 2019. Cash Flow Statement In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows: Classification of Certain Cash Receipts and Cash Payments (ASC 230), which addresses the classification and presentation of certain items, including debt prepayment and extinguishment costs, contingent consideration payments made after a business combination and distributions received from equity method investees, for which there was diversity in practice. In November 2016, the FASB issued ASU 2016-18, Statement of Cash Flows: Restricted Cash (ASC 230). Under current guidance, restricted amounts of cash or cash equivalents are excluded from the cash flow statement. The new guidance requires restricted cash and restricted cash equivalents to be included in the reconciliation of beginning and end-of-period amounts presented on the statement of cash flows. In addition, the new guidance requires a description of the nature of the changes in restricted cash and cash equivalents during the periods presented. The updated guidance in ASU 2016-15 and ASU 2016-18 are both effective for interim and annual reporting periods beginning after December 15, 2017, with early adoption permitted. White Mountains does not expect adoption to have any effect on its financial statements. Credit Losses In June 2016, the FASB issued ASU 2016-13, Measurement of Credit Losses on Financial Instruments (ASC 326), which establishes new guidance for the recognition of credit losses for financial assets measured at amortized cost. The new ASU requires reporting entities to estimate the credit losses expected over the life of a credit exposure using historical information, current information and reasonable and supportable forecasts that affect the collectability of the financial asset. This differs from current GAAP, which delays recognition until it is probable a loss has been incurred. The new guidance is expected to accelerate recognition of credit losses. The types of assets within the scope of the new guidance include loans and trade receivables such as premium receivables and reinsurance recoverables on paid losses. ASU 2016-13 is effective for annual periods beginning after January 1, 2020, including interim periods. White Mountains measures its portfolio of investment securities at fair value with changes therein recognized through current period earnings and accordingly does not expect adoption to have any effect on its financial statements. Leases In February 2016, the FASB issued ASU 2016-02, Leases (ASC 842). The new guidance requires lessees to recognize lease assets and liabilities on the balance sheet for both operating and financing leases, with the exception of leases with an original term of 12 months or less. Under existing guidance recognition of lease assets and liabilities is not required for operating leases. The lease assets and liabilities to be recognized are both measured initially based on the present value of the lease payments. Under the new guidance, a sale-leaseback transaction must meet the recognition criteria under ASC 606, Revenues, in order to be accounted for as sale. The new guidance is effective for White Mountains for years beginning after December 15, 2018, including interim periods therein. White Mountains is evaluating the expected impact of this guidance and available adoption methods. Financial Instruments - Recognition and Measurement In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (ASC 825-10). The new ASU modifies the guidance for financial instruments, including investments in equity securities. Under the new guidance, all equity securities with readily determinable fair values are required to be measured at fair value with changes therein recognized through current period earnings. In addition, the new ASU requires a qualitative assessment for equity securities without readily determinable fair values to identify impairment, and for impaired equity securities to be measured at fair value. ASU 2016-01 is effective for fiscal years beginning after December 15, 2017, with early adoption permitted. White Mountains measures its portfolio of investment securities at fair value with changes therein recognized through current period earnings and accordingly, does not expect adoption to have any effect on its financial statements.

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