Organization and Summary of Significant Accounting Policies	12 Months Ended
Dec. 31, 2011
Organization and Summary of Significant Accounting Policies	Note 1. Organization and Summary of Significant Accounting Policies *Organization* The accompanying consolidated financial statements, consisting of the accounts of The Navigators Group, Inc., a Delaware holding company established in 1982, and its wholly-owned subsidiaries, are prepared on the basis of U.S. generally accepted accounting principles (“GAAP” or “U.S. GAAP”). The terms “we”, “us”, “our” and “the Company” as used herein are used to mean The Navigators Group, Inc. and its subsidiaries, unless the context otherwise requires. The terms “Parent” or “Parent Company” are used to mean The Navigators Group, Inc. without its subsidiaries. All significant intercompany transactions and balances have been eliminated. Certain amounts for prior years have been reclassified to conform to the current year’s presentation. Commission income, previously disclosed as a separate line item in the Consolidated Statements of Income, is now included in Other income (expense). We are an international insurance company focusing on specialty products within the overall property and casualty insurance market. Our largest product line and most long-standing area of specialization is ocean marine insurance. We have also developed specialty niches in professional liability insurance as well as other specialty insurance lines such as contractors’ liability and commercial primary and excess liability coverages. Our revenue is primarily comprised of premiums and investment income. We derive our premiums primarily from business written by wholly-owned underwriting management companies which produce, manage and underwrite insurance and reinsurance for us. Our products are distributed through multiple channels, utilizing global, national and regional retail and wholesale insurance brokers. We conduct operations through our Insurance Companies and our Lloyd’s Operations segments. The Insurance Companies segment consists of Navigators Insurance Company, which includes a United Kingdom Branch (the “U.K. Branch”), and Navigators Specialty Insurance Company, which underwrites specialty and professional liability insurance on an excess and surplus lines basis. All of the insurance business written by Navigators Specialty Insurance Company is fully reinsured by Navigators Insurance Company pursuant to a 100% quota share reinsurance agreement. Our Lloyd’s Operations segment includes Navigators Underwriting Agency Ltd. (“NUAL”), a Lloyd’s of London (“Lloyd’s”) underwriting agency which manages Lloyd’s Syndicate 1221 (“Syndicate 1221”). Our Lloyd’s Operations primarily underwrite marine and related lines of business along with offshore energy, professional liability insurance and construction coverages for onshore energy business at Lloyd’s through Syndicate 1221. We controlled 100% of Syndicate 1221’s stamp capacity for the 2011, 2010 and 2009 underwriting years through our wholly owned subsidiary, Navigators Corporate Underwriters Ltd., which is referred to as a corporate name in the Lloyd’s market. We have also established underwriting agencies in Antwerp, Belgium, Stockholm, Sweden and Copenhagen, Denmark, which underwrite risks pursuant to binding authorities with NUAL into Syndicate 1221. For financial information by segment, refer to Note 3, Segment Information, to the Consolidated Financial Statements. *Significant Accounting Policies* Cash Cash includes cash on hand, demand deposits with banks and treasury bills with original maturities of less than 90 days. Investments As of December 31, 2011 and 2010, all fixed maturity and equity securities held by the Company were carried at fair value and classified as available-for-sale. Available-for-sale securities are debt and equity securities not classified as either held-to-maturity securities or trading securities and are reported at fair value, with unrealized gains and losses excluded from earnings and reported in other comprehensive income as a separate component of stockholders’ equity. Fixed maturity securities include bonds, mortgage-backed and asset-backed securities. Equity securities consist of common stock. Short-term investments are carried at cost, which approximates fair value. Short-term investments mature within one year from the purchase date. All prices for our fixed maturities, equity securities and short-term investments valued as Level 1, Level 2 or Level 3 in the fair value hierarchy, as defined in the Financial Accounts Standards Board (“FASB”) Accounting Standards Codification 820 (“ASC 820”), Fair Value Measurements, are received from independent pricing services utilized by one of our outside investment managers whom we employ to assist us with investment accounting services. This manager utilizes a pricing committee which approves the use of one or more independent pricing service vendors. The pricing committee consists of five or more members of the investment management firm, one from senior management and one from the accounting group with the remainder from the asset class specialists and client strategists. The pricing source of each security is determined in accordance with the pricing source procedures approved by the pricing committee. The investment manager uses supporting documentation received from the independent pricing service vendor detailing the inputs, models and processes used in the independent pricing service vendors’ evaluation process to determine the appropriate fair value hierarchy. Any pricing where the input is based solely on a broker price is deemed to be a Level 3 price. Management has reviewed this process by which the manager determines the prices and has obtained alternative pricing to validate a sample of the prices and assess their reasonableness. Premiums and discounts on fixed maturity securities are amortized into interest income over the life of the security under the interest method. For mortgage-backed and asset-backed securities, anticipated prepayments and expected maturities are utilized in applying the interest rate method to our mortgage-backed and asset-backed securities. An effective yield is calculated based on projected principal cash flows at the time of original purchase. The effective yield is used to amortize the purchase price of the security over the security’s expected life. Book values are adjusted to reflect the amortization of premium or accretion of discount on a monthly basis. The projected principal cash flows are based on certain prepayment assumptions which are generated using a prepayment model. The prepayment model uses a number of factors to estimate prepayment activity including the current levels of interest rates (refinancing incentive), time of year (seasonality), economic activity (including housing turnover) and term and age of the underlying collateral (burnout, seasoning). Prepayment assumptions associated with the mortgage-backed and asset-backed securities are reviewed on a periodic basis. When changes in prepayment assumptions are deemed necessary as the result of actual prepayments differing from anticipated prepayments, securities are revalued based upon the new prepayment assumptions utilizing the retrospective adjustment method, whereby the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The investment in such securities is adjusted to the amount that would have existed had the new effective yield been applied since the acquisition of the security. Such adjustments, if any, are included in net investment income for the current period being reported. Realized gains and losses on sales of investments are recognized when the related trades are executed and are determined on the basis of the specific identification method. *Impairment of Invested Assets* Management regularly reviews our fixed maturity and equity securities portfolios to evaluate the necessity of recording impairment losses for other-than-temporary declines in the fair value of securities. For fixed maturity securities, we consider our intent to sell a security and whether it is more likely than not that we will be required to sell a security before the anticipated recovery as part of the process of evaluating whether a security’s unrealized loss represents an other-than-temporary decline. We assess whether the amortized cost basis of a fixed maturity security will be recovered by comparing the present value of cash flows expected to be collected to the current book value. Any shortfalls of the present value of the cash flows expected to be collected in relation to the amortized cost basis is considered the credit loss portion of other-than-temporary impairment (“OTTI”) losses and is recognized in earnings. All non-credit losses are recognized as changes in OTTI losses within Other Comprehensive Income (“OCI”). For equity securities, in general, we focus our attention on those securities whose fair value was less than 80% of their cost for six or more consecutive months. If warranted as the result of conditions relating to a particular security, we will focus on a significant decline in fair value regardless of the time period involved. Factors considered in evaluating potential impairment include, but are not limited to, the current fair value as compared to cost of the security, the length of time the investment has been below cost and the impact of the amount. If an equity security is deemed to be other-than-temporarily impaired, the cost is written down to fair value with the loss recognized in earnings. For equity securities, we also consider our intent to hold securities as part of the process of evaluating whether a decline in fair value represents an other-than-temporary decline in value. For fixed maturity securities, we consider our intent to sell a security and whether it is more likely than not that we will be required to sell a security before the anticipated recovery as part of the process of evaluating whether a security’s unrealized loss represents an other-than-temporary decline. Our ability to hold such securities is evaluated by the Company and is based on whether there is sufficient cash flow from operations and from maturities within our investment portfolio in order to meet claims payment and other disbursement obligations arising from our underwriting operations without selling such investments. With respect to securities where the decline in value is determined to be temporary and the security’s value is not written down, a subsequent decision may be made to sell that security and realize a loss. Subsequent decisions on security sales are made within the context of overall risk monitoring, changing information and market conditions. The day to day management of our investment portfolio is outsourced to third party investment managers. While these investment managers may, at a given point in time, believe that the preferred course of action is to hold securities with unrealized losses that are considered temporary until such losses are recovered, the dynamic nature of the portfolio management may result in a subsequent decision to sell the security and realize the loss based upon a change in the market and other factors described above. Investment managers are required to notify management of rating agency downgrades of securities in their portfolios as well as any potential investment valuation issues at the end of each quarter. Investment managers are also required to notify management, and receive approval, prior to the execution of a transaction or series of related transactions that may result in a realized loss above a certain threshold. Additionally, management monitors the execution of a transaction or series of related transactions that may result in any realized loss up until a certain period beyond the close of a quarterly accounting period. Syndicate 1221 We record Syndicate 1221’s assets, liabilities, revenues and expenses under U.S. GAAP. We record adjustments to recognize underwriting results as incurred, including the ultimate cost of losses incurred. These adjustments to losses are based on actuarial analysis of Syndicate 1221’s accounts, including forecasts of expected ultimate losses. Translation of Foreign Currencies Functional currency assets and liabilities are translated into U.S. dollars using period end rates of exchange and the related translation adjustments are recorded as a separate component of Accumulated other comprehensive income. Statement of income amounts expressed in functional currencies are translated using average exchange rates. Realized gains and losses resulting from foreign currency transactions are recorded in Other income (expense) in our Consolidated Statements of Income. Premium Revenues Written premium is recorded based on the insurance policies that have been reported to us and the policies that have been written by agents but not yet reported to us. We must estimate the amount of written premium not yet reported based on judgments relative to current and historical trends of the business being written. Such estimates are regularly reviewed and updated and any resulting adjustments are included in the current year’s results. An unearned premium reserve is established to reflect the unexpired portion of each policy at the financial reporting date. Substantially all of our business is placed through agents and brokers. Since the majority of our gross written premiums are primary or direct, as opposed to assumed, the delays in reporting assumed premiums generally do not have a significant effect on our financial statements, as we record estimates for both unreported direct and assumed premiums. We also record the ceded portion of the estimated gross written premium and related acquisition costs. The earned gross, ceded and net premiums are calculated based on our earning methodology which is generally pro-rata over the policy period or over the period of risk if the period of risk differs significantly from the contract period. Losses are also recorded in relation to the earned premium. The estimate for losses incurred on the estimated premium is based on an actuarial calculation consistent with the methodology used to determine incurred but not reported (“IBNR”) loss reserves for reported premiums. A portion of our premium is estimated for unreported premium, mostly for the marine business written by our U.K. Branch and Lloyd’s Operations as well as the accident and health reinsurance business written by our recently established reinsurance division Navigators Reinsurance. We generally do not experience any significant backlog in processing premiums. Such premium estimates are generally based on submission data received from brokers and agents and recorded when the insurance policy or reinsurance contract is written or bound. The estimates are regularly reviewed and updated taking into account the premium received to date versus the estimate and the age of the estimate. To the extent that the actual premium varies from the estimates, the difference, along with the related loss reserves and underwriting expenses, is recorded in current operations. Reinsurance Ceded In the normal course of business, reinsurance is purchased by us from insurers or reinsurers to reduce the amount of loss arising from claims. In order to determine the proper accounting for the reinsurance, management analyzes the reinsurance agreements to determine whether the reinsurance should be classified as prospective or retroactive based upon the terms of the reinsurance agreement and whether the reinsurer has assumed significant insurance risk to the extent that the reinsurer may realize a significant loss from the transaction. Prospective reinsurance is reinsurance in which an assuming company agrees to reimburse the ceding company for losses that may be incurred as a result of future insurable events covered under contracts subject to the reinsurance. Retroactive reinsurance is reinsurance in which an assuming company agrees to reimburse a ceding company for liabilities incurred as a result of past insurable events covered under contracts subject to the reinsurance. The analysis of the reinsurance contract terms has determined that all of our reinsurance is prospective reinsurance with adequate transfer of insurance risk to the reinsurer to qualify for reinsurance accounting treatment. Ceded reinsurance premiums and any related ceding commission and ceded losses are reflected as reductions of the respective income or expense accounts over the terms of the reinsurance contracts. Prepaid reinsurance premiums represent the portion of premiums ceded to reinsurers applicable to the unexpired terms of the reinsurance contracts in force. Reinsurance reinstatement premiums are recognized in the same period as the loss event that gave rise to the reinstatement premiums. Amounts recoverable from reinsurers are estimated in a manner consistent with the claim liability associated with the reinsured policy. Unearned premiums ceded and estimates of amounts recoverable from reinsurers on paid and unpaid losses are reflected as assets. Provisions are made for estimated unrecoverable reinsurance. Deferred Policy Acquisition Costs Costs of acquiring business which vary with and are directly related to the production of business are deferred and amortized ratably over the period that the related premiums are recognized as revenue. Such costs primarily include commission expense, other underwriting expenses and premium taxes. The method of computing deferred policy acquisition costs limits the deferral to their estimated net realizable value based on the related unearned premiums and takes into account anticipated losses and loss adjustment expenses, commission expense and operating expenses based on historical and current experience as well as anticipated investment income. Reserves for Losses and Loss Adjustment Expenses Unpaid losses and loss adjustment expenses are determined on an individual basis for claims reported on direct business for insureds, from reports received from ceding insurers for insurance assumed from such insurers and on estimates based on Company and industry experience for IBNR claims and loss adjustment expenses. Indicated IBNR loss reserves are calculated by our actuaries using several standard actuarial methodologies, including the paid and incurred loss development and the paid and incurred Bornheutter-Ferguson loss methods. Additional analyses, such as frequency/severity analyses, are performed for certain books of business. The provision for unpaid losses and loss adjustment expenses has been established to cover the estimated unpaid cost of claims incurred. Such estimates are regularly reviewed and updated and any resulting adjustments are included in the current year’s results. Management believes that the liability it has recognized for unpaid losses and loss adjustment expenses is a reasonable estimate of the ultimate unpaid claims incurred, however, such provisions are necessarily based on estimates and, accordingly, no representation is made that the ultimate liability will not differ materially from the amounts recorded in the accompanying consolidated financial statements. Losses and loss adjustment expenses are recorded on an undiscounted basis. Earnings per Share Basic earnings per share (“EPS”) is computed by dividing net income by the weighted average number of common shares outstanding for the period. Diluted earnings per share reflects the basic earnings per share adjusted for the potential dilution that would occur if all issued stock options were exercised and all stock grants were fully vested. Depreciation and Amortization Depreciation of furniture and fixtures, electronic data processing equipment and computer software is provided over the estimated useful lives of the respective assets, ranging from three to seven years, using the straight-line method. Amortization of leasehold improvements is provided over the shorter of the useful lives of those improvements or the contractual terms of the leases using the straight-line method. Goodwill and Other Intangible Assets Goodwill and other intangible assets were $6.9 million as of December 31, 2011 and 2010, respectively. The goodwill and other intangible assets consist of $2.5 million for the underwriting agencies as of December 31, 2011 and 2010, respectively and $4.3 million and $4.4 million for the Lloyd’s Operations as of December 31, 2011 and 2010, respectively. The December 31, 2011 and 2010 goodwill and other intangible assets of $6.9 million consisted of $4.8 million of goodwill and $2.1 million of indefinite lived intangible assets, respectively. Goodwill and other intangible assets on the Company’s Consolidated Balance Sheets are not amortized and may fluctuate due to changes in the currency exchange rates between the U.S. dollar and the British pound. We completed our annual impairment review of goodwill and other intangible assets which did not result in an impairment as of December 31, 2011. Income Taxes We apply the asset and liability method of accounting for income taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. 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 at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. In addition to all of our reserves for losses and loss adjustment expenses being an estimate, a portion of our premiums are estimated for unreported premiums, mostly for the marine business written by our U.K. Branch and Lloyd’s Operations. We generally do not experience any significant backlog in processing premiums. Such premium estimates are generally based on submission data received from brokers and agents and recorded when the insurance policy or reinsurance contract is bound and written. The estimates are regularly reviewed and updated taking into account the premium received to date versus the estimate and the age of the estimate. To the extent that the actual premium varies from the estimates, the difference, along with the related loss reserves and underwriting expenses, is recorded in current operations. *Recently Adopted Accounting Pronouncements* In January 2010, the Financial Accounting Standards Board (“FASB”) issued accounting guidance (Accounting Standards Update (“ASU”) 2010-06) which improves disclosures about fair value measurements (Accounting Standards Codification (“ASC” or “Codification”) 820-10). This guidance requires additional disclosures regarding significant transfers in and out of Levels 1 and 2 and additional disclosures regarding Level 3 purchases, sales, issuances and settlements. In addition, this guidance also requires fair value measurement disclosures for each class of assets and liabilities as well as disclosures about the valuation techniques and inputs used to measure fair value for items classified as Level 2 or Level 3. This guidance was effective as of January 1, 2010 for calendar year reporting entities with the exception of the additional disclosures about purchases, sales, issuances and settlements in the roll forward of activity in Level 3 fair value measurements which became effective as of January 1, 2011 for calendar year reporting entities. Early adoption was permitted. The Company adopted this guidance in the first quarter of 2010 with the exception of the additional disclosures about purchases, sales, issuances and settlement in the roll forward of activity in Level 3 fair value measurements, which the Company adopted in the first quarter of 2011. Adoption of this guidance did not have a material effect on the Company’s consolidated financial condition, results of operations or cash flows. *Recent Accounting Developments* In September 2011, the FASB issued ASU 2011-08 amending Codification topic 350 – Intangibles – Goodwill and Other. The amendment simplifies how goodwill is tested for impairment by permitting entities to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying value as a basis for determining whether it is necessary to perform the two step goodwill impairment test. The amendment is effective for the interim and annual goodwill impairment tests performed for fiscal years beginning after December 15, 2011. Early adoption is permitted, but the Company did not early adopt. Adoption of this guidance is not expected to have a material effect on the Company’s consolidated financial condition, results of operations or cash flows. In June 2011, the FASB issued ASU 2011-05 amending Codification Topic 220—Comprehensive Income. The amendment requires that other comprehensive income be either presented in a single continuous statement or two separate but consecutive statements. In addition, the amendment requires the disclosure of reclassification adjustments for items reclassified from other comprehensive income to net income on the face of the financial statements. The amendment is effective for the interim and annual periods beginning after December 15, 2011 and should be applied retrospectively. This standard will only affect the Company’s presentation of comprehensive income and will not affect the Company’s financial position, results of operations, and cash flows. In May 2011, the FASB issued ASU 2011-04 amending Codification Topic 820—Fair Value Measurements and Disclosures. The amendments were intended to result in common fair value measurement and disclosure requirements in U.S. GAAP and International Financial Reporting Standards (“IFRS”). The amendment expands and enhances current disclosures about fair value measurement and clarifies the FASB’s intent regarding the application of existing fair value measurement requirements in certain circumstances. The amendments are effective for the interim and annual periods beginning after December 15, 2011 and should be applied prospectively. We are currently evaluating the impact of this amendment on the Company’s consolidated financial position, results of operations and cash flows. In October 2010, the FASB issued ASU 2010-26 amending Codification Topic 944 – Financial Services – Insurance; Accounting for Costs Associated with Acquiring or Renewing Insurance Contracts. The amendment clarifies which costs relating to the acquisition of new or renewal insurance contracts qualify for deferral. In addition, the amendment limits deferrable costs that can be capitalized to those that are incremental direct costs related to the successful acquisition of new or renewal insurance contracts. The amendment is effective for fiscal years and interim periods within a fiscal year, beginning after December 15, 2011. The guidance is to be applied prospectively upon effectiveness of the amendment, with retrospective application permitted, but not required. The Company did not early adopt. The Company will adopt this guidance prospectively in the first quarter of 2012. Adoption of this guidance is not expected to have a material effect on the Company’s consolidated financial condition, results of operations or cash flows.

Note 1. Organization and Summary of Significant Accounting Policies

Organization

The accompanying consolidated financial statements, consisting of the accounts of The Navigators Group, Inc., a Delaware holding company established in 1982, and its wholly-owned subsidiaries, are prepared on the basis of U.S. generally accepted accounting principles (“GAAP” or “U.S. GAAP”). The terms “we”, “us”, “our” and “the Company” as used herein are used to mean The Navigators Group, Inc. and its subsidiaries, unless the context otherwise requires. The terms “Parent” or “Parent Company” are used to mean The Navigators Group, Inc. without its subsidiaries. All significant intercompany transactions and balances have been eliminated. Certain amounts for prior years have been reclassified to conform to the current year’s presentation. Commission income, previously disclosed as a separate line item in the Consolidated Statements of Income, is now included in Other income (expense).

We are an international insurance company focusing on specialty products within the overall property and casualty insurance market. Our largest product line and most long-standing area of specialization is ocean marine insurance. We have also developed specialty niches in professional liability insurance as well as other specialty insurance lines such as contractors’ liability and commercial primary and excess liability coverages.

Our revenue is primarily comprised of premiums and investment income. We derive our premiums primarily from business written by wholly-owned underwriting management companies which produce, manage and underwrite insurance and reinsurance for us. Our products are distributed through multiple channels, utilizing global, national and regional retail and wholesale insurance brokers.

We conduct operations through our Insurance Companies and our Lloyd’s Operations segments. The Insurance Companies segment consists of Navigators Insurance Company, which includes a United Kingdom Branch (the “U.K. Branch”), and Navigators Specialty Insurance Company, which underwrites specialty and professional liability insurance on an excess and surplus lines basis. All of the insurance business written by Navigators Specialty Insurance Company is fully reinsured by Navigators Insurance Company pursuant to a 100% quota share reinsurance agreement. Our Lloyd’s Operations segment includes Navigators Underwriting Agency Ltd. (“NUAL”), a Lloyd’s of London (“Lloyd’s”) underwriting agency which manages Lloyd’s Syndicate 1221 (“Syndicate 1221”). Our Lloyd’s Operations primarily underwrite marine and related lines of business along with offshore energy, professional liability insurance and construction coverages for onshore energy business at Lloyd’s through Syndicate 1221. We controlled 100% of Syndicate 1221’s stamp capacity for the 2011, 2010 and 2009 underwriting years through our wholly owned subsidiary, Navigators Corporate Underwriters Ltd., which is referred to as a corporate name in the Lloyd’s market. We have also established underwriting agencies in Antwerp, Belgium, Stockholm, Sweden and Copenhagen, Denmark, which underwrite risks pursuant to binding authorities with NUAL into Syndicate 1221. For financial information by segment, refer to Note 3, Segment Information, to the Consolidated Financial Statements.

Significant Accounting Policies

Cash

Cash includes cash on hand, demand deposits with banks and treasury bills with original maturities of less than 90 days.

Investments

As of December 31, 2011 and 2010, all fixed maturity and equity securities held by the Company were carried at fair value and classified as available-for-sale. Available-for-sale securities are debt and equity securities not classified as either held-to-maturity securities or trading securities and are reported at fair value, with unrealized gains and losses excluded from earnings and reported in other comprehensive income as a separate component of stockholders’ equity. Fixed maturity securities include bonds, mortgage-backed and asset-backed securities. Equity securities consist of common stock.

Short-term investments are carried at cost, which approximates fair value. Short-term investments mature within one year from the purchase date.

All prices for our fixed maturities, equity securities and short-term investments valued as Level 1, Level 2 or Level 3 in the fair value hierarchy, as defined in the Financial Accounts Standards Board (“FASB”) Accounting Standards Codification 820 (“ASC 820”), Fair Value Measurements, are received from independent pricing services utilized by one of our outside investment managers whom we employ to assist us with investment accounting services. This manager utilizes a pricing committee which approves the use of one or more independent pricing service vendors. The pricing committee consists of five or more members of the investment management firm, one from senior management and one from the accounting group with the remainder from the asset class specialists and client strategists. The pricing source of each security is determined in accordance with the pricing source procedures approved by the pricing committee. The investment manager uses supporting documentation received from the independent pricing service vendor detailing the inputs, models and processes used in the independent pricing service vendors’ evaluation process to determine the appropriate fair value hierarchy. Any pricing where the input is based solely on a broker price is deemed to be a Level 3 price. Management has reviewed this process by which the manager determines the prices and has obtained alternative pricing to validate a sample of the prices and assess their reasonableness.

Premiums and discounts on fixed maturity securities are amortized into interest income over the life of the security under the interest method. For mortgage-backed and asset-backed securities, anticipated prepayments and expected maturities are utilized in applying the interest rate method to our mortgage-backed and asset-backed securities. An effective yield is calculated based on projected principal cash flows at the time of original purchase. The effective yield is used to amortize the purchase price of the security over the security’s expected life. Book values are adjusted to reflect the amortization of premium or accretion of discount on a monthly basis. The projected principal cash flows are based on certain prepayment assumptions which are generated using a prepayment model. The prepayment model uses a number of factors to estimate prepayment activity including the current levels of interest rates (refinancing incentive), time of year (seasonality), economic activity (including housing turnover) and term and age of the underlying collateral (burnout, seasoning). Prepayment assumptions associated with the mortgage-backed and asset-backed securities are reviewed on a periodic basis. When changes in prepayment assumptions are deemed necessary as the result of actual prepayments differing from anticipated prepayments, securities are revalued based upon the new prepayment assumptions utilizing the retrospective adjustment method, whereby the effective yield is recalculated to reflect actual payments to date and anticipated future payments. The investment in such securities is adjusted to the amount that would have existed had the new effective yield been applied since the acquisition of the security. Such adjustments, if any, are included in net investment income for the current period being reported.

Realized gains and losses on sales of investments are recognized when the related trades are executed and are determined on the basis of the specific identification method.

Impairment of Invested Assets

Management regularly reviews our fixed maturity and equity securities portfolios to evaluate the necessity of recording impairment losses for other-than-temporary declines in the fair value of securities.

For fixed maturity securities, we consider our intent to sell a security and whether it is more likely than not that we will be required to sell a security before the anticipated recovery as part of the process of evaluating whether a security’s unrealized loss represents an other-than-temporary decline. We assess whether the amortized cost basis of a fixed maturity security will be recovered by comparing the present value of cash flows expected to be collected to the current book value. Any shortfalls of the present value of the cash flows expected to be collected in relation to the amortized cost basis is considered the credit loss portion of other-than-temporary impairment (“OTTI”) losses and is recognized in earnings. All non-credit losses are recognized as changes in OTTI losses within Other Comprehensive Income (“OCI”).

For equity securities, in general, we focus our attention on those securities whose fair value was less than 80% of their cost for six or more consecutive months. If warranted as the result of conditions relating to a particular security, we will focus on a significant decline in fair value regardless of the time period involved. Factors considered in evaluating potential impairment include, but are not limited to, the current fair value as compared to cost of the security, the length of time the investment has been below cost and the impact of the amount. If an equity security is deemed to be other-than-temporarily impaired, the cost is written down to fair value with the loss recognized in earnings.

For equity securities, we also consider our intent to hold securities as part of the process of evaluating whether a decline in fair value represents an other-than-temporary decline in value. For fixed maturity securities, we consider our intent to sell a security and whether it is more likely than not that we will be required to sell a security before the anticipated recovery as part of the process of evaluating whether a security’s unrealized loss represents an other-than-temporary decline. Our ability to hold such securities is evaluated by the Company and is based on whether there is sufficient cash flow from operations and from maturities within our investment portfolio in order to meet claims payment and other disbursement obligations arising from our underwriting operations without selling such investments. With respect to securities where the decline in value is determined to be temporary and the security’s value is not written down, a subsequent decision may be made to sell that security and realize a loss. Subsequent decisions on security sales are made within the context of overall risk monitoring, changing information and market conditions.

The day to day management of our investment portfolio is outsourced to third party investment managers. While these investment managers may, at a given point in time, believe that the preferred course of action is to hold securities with unrealized losses that are considered temporary until such losses are recovered, the dynamic nature of the portfolio management may result in a subsequent decision to sell the security and realize the loss based upon a change in the market and other factors described above. Investment managers are required to notify management of rating agency downgrades of securities in their portfolios as well as any potential investment valuation issues at the end of each quarter. Investment managers are also required to notify management, and receive approval, prior to the execution of a transaction or series of related transactions that may result in a realized loss above a certain threshold. Additionally, management monitors the execution of a transaction or series of related transactions that may result in any realized loss up until a certain period beyond the close of a quarterly accounting period.

Syndicate 1221

We record Syndicate 1221’s assets, liabilities, revenues and expenses under U.S. GAAP. We record adjustments to recognize underwriting results as incurred, including the ultimate cost of losses incurred. These adjustments to losses are based on actuarial analysis of Syndicate 1221’s accounts, including forecasts of expected ultimate losses.

Translation of Foreign Currencies

Functional currency assets and liabilities are translated into U.S. dollars using period end rates of exchange and the related translation adjustments are recorded as a separate component of Accumulated other comprehensive income. Statement of income amounts expressed in functional currencies are translated using average exchange rates. Realized gains and losses resulting from foreign currency transactions are recorded in Other income (expense) in our Consolidated Statements of Income.

Premium Revenues

Written premium is recorded based on the insurance policies that have been reported to us and the policies that have been written by agents but not yet reported to us. We must estimate the amount of written premium not yet reported based on judgments relative to current and historical trends of the business being written. Such estimates are regularly reviewed and updated and any resulting adjustments are included in the current year’s results. An unearned premium reserve is established to reflect the unexpired portion of each policy at the financial reporting date.

Substantially all of our business is placed through agents and brokers. Since the majority of our gross written premiums are primary or direct, as opposed to assumed, the delays in reporting assumed premiums generally do not have a significant effect on our financial statements, as we record estimates for both unreported direct and assumed premiums. We also record the ceded portion of the estimated gross written premium and related acquisition costs. The earned gross, ceded and net premiums are calculated based on our earning methodology which is generally pro-rata over the policy period or over the period of risk if the period of risk differs significantly from the contract period. Losses are also recorded in relation to the earned premium. The estimate for losses incurred on the estimated premium is based on an actuarial calculation consistent with the methodology used to determine incurred but not reported (“IBNR”) loss reserves for reported premiums.

A portion of our premium is estimated for unreported premium, mostly for the marine business written by our U.K. Branch and Lloyd’s Operations as well as the accident and health reinsurance business written by our recently established reinsurance division Navigators Reinsurance. We generally do not experience any significant backlog in processing premiums. Such premium estimates are generally based on submission data received from brokers and agents and recorded when the insurance policy or reinsurance contract is written or bound. The estimates are regularly reviewed and updated taking into account the premium received to date versus the estimate and the age of the estimate. To the extent that the actual premium varies from the estimates, the difference, along with the related loss reserves and underwriting expenses, is recorded in current operations.

Reinsurance Ceded

In the normal course of business, reinsurance is purchased by us from insurers or reinsurers to reduce the amount of loss arising from claims. In order to determine the proper accounting for the reinsurance, management analyzes the reinsurance agreements to determine whether the reinsurance should be classified as prospective or retroactive based upon the terms of the reinsurance agreement and whether the reinsurer has assumed significant insurance risk to the extent that the reinsurer may realize a significant loss from the transaction.

Prospective reinsurance is reinsurance in which an assuming company agrees to reimburse the ceding company for losses that may be incurred as a result of future insurable events covered under contracts subject to the reinsurance. Retroactive reinsurance is reinsurance in which an assuming company agrees to reimburse a ceding company for liabilities incurred as a result of past insurable events covered under contracts subject to the reinsurance. The analysis of the reinsurance contract terms has determined that all of our reinsurance is prospective reinsurance with adequate transfer of insurance risk to the reinsurer to qualify for reinsurance accounting treatment.

Ceded reinsurance premiums and any related ceding commission and ceded losses are reflected as reductions of the respective income or expense accounts over the terms of the reinsurance contracts. Prepaid reinsurance premiums represent the portion of premiums ceded to reinsurers applicable to the unexpired terms of the reinsurance contracts in force. Reinsurance reinstatement premiums are recognized in the same period as the loss event that gave rise to the reinstatement premiums. Amounts recoverable from reinsurers are estimated in a manner consistent with the claim liability associated with the reinsured policy. Unearned premiums ceded and estimates of amounts recoverable from reinsurers on paid and unpaid losses are reflected as assets. Provisions are made for estimated unrecoverable reinsurance.

Deferred Policy Acquisition Costs

Costs of acquiring business which vary with and are directly related to the production of business are deferred and amortized ratably over the period that the related premiums are recognized as revenue. Such costs primarily include commission expense, other underwriting expenses and premium taxes. The method of computing deferred policy acquisition costs limits the deferral to their estimated net realizable value based on the related unearned premiums and takes into account anticipated losses and loss adjustment expenses, commission expense and operating expenses based on historical and current experience as well as anticipated investment income.

Reserves for Losses and Loss Adjustment Expenses

Unpaid losses and loss adjustment expenses are determined on an individual basis for claims reported on direct business for insureds, from reports received from ceding insurers for insurance assumed from such insurers and on estimates based on Company and industry experience for IBNR claims and loss adjustment expenses. Indicated IBNR loss reserves are calculated by our actuaries using several standard actuarial methodologies, including the paid and incurred loss development and the paid and incurred Bornheutter-Ferguson loss methods. Additional analyses, such as frequency/severity analyses, are performed for certain books of business. The provision for unpaid losses and loss adjustment expenses has been established to cover the estimated unpaid cost of claims incurred. Such estimates are regularly reviewed and updated and any resulting adjustments are included in the current year’s results. Management believes that the liability it has recognized for unpaid losses and loss adjustment expenses is a reasonable estimate of the ultimate unpaid claims incurred, however, such provisions are necessarily based on estimates and, accordingly, no representation is made that the ultimate liability will not differ materially from the amounts recorded in the accompanying consolidated financial statements. Losses and loss adjustment expenses are recorded on an undiscounted basis.

Earnings per Share

Basic earnings per share (“EPS”) is computed by dividing net income by the weighted average number of common shares outstanding for the period. Diluted earnings per share reflects the basic earnings per share adjusted for the potential dilution that would occur if all issued stock options were exercised and all stock grants were fully vested.

Depreciation and Amortization

Depreciation of furniture and fixtures, electronic data processing equipment and computer software is provided over the estimated useful lives of the respective assets, ranging from three to seven years, using the straight-line method. Amortization of leasehold improvements is provided over the shorter of the useful lives of those improvements or the contractual terms of the leases using the straight-line method.

Goodwill and Other Intangible Assets

Goodwill and other intangible assets were $6.9 million as of December 31, 2011 and 2010, respectively. The goodwill and other intangible assets consist of $2.5 million for the underwriting agencies as of December 31, 2011 and 2010, respectively and $4.3 million and $4.4 million for the Lloyd’s Operations as of December 31, 2011 and 2010, respectively. The December 31, 2011 and 2010 goodwill and other intangible assets of $6.9 million consisted of $4.8 million of goodwill and $2.1 million of indefinite lived intangible assets, respectively. Goodwill and other intangible assets on the Company’s Consolidated Balance Sheets are not amortized and may fluctuate due to changes in the currency exchange rates between the U.S. dollar and the British pound.

We completed our annual impairment review of goodwill and other intangible assets which did not result in an impairment as of December 31, 2011.

Income Taxes

We apply the asset and liability method of accounting for income taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.

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 at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. In addition to all of our reserves for losses and loss adjustment expenses being an estimate, a portion of our premiums are estimated for unreported premiums, mostly for the marine business written by our U.K. Branch and Lloyd’s Operations. We generally do not experience any significant backlog in processing premiums. Such premium estimates are generally based on submission data received from brokers and agents and recorded when the insurance policy or reinsurance contract is bound and written. The estimates are regularly reviewed and updated taking into account the premium received to date versus the estimate and the age of the estimate. To the extent that the actual premium varies from the estimates, the difference, along with the related loss reserves and underwriting expenses, is recorded in current operations.

Recently Adopted Accounting Pronouncements

In January 2010, the Financial Accounting Standards Board (“FASB”) issued accounting guidance (Accounting Standards Update (“ASU”) 2010-06) which improves disclosures about fair value measurements (Accounting Standards Codification (“ASC” or “Codification”) 820-10). This guidance requires additional disclosures regarding significant transfers in and out of Levels 1 and 2 and additional disclosures regarding Level 3 purchases, sales, issuances and settlements. In addition, this guidance also requires fair value measurement disclosures for each class of assets and liabilities as well as disclosures about the valuation techniques and inputs used to measure fair value for items classified as Level 2 or Level 3. This guidance was effective as of January 1, 2010 for calendar year reporting entities with the exception of the additional disclosures about purchases, sales, issuances and settlements in the roll forward of activity in Level 3 fair value measurements which became effective as of January 1, 2011 for calendar year reporting entities. Early adoption was permitted. The Company adopted this guidance in the first quarter of 2010 with the exception of the additional disclosures about purchases, sales, issuances and settlement in the roll forward of activity in Level 3 fair value measurements, which the Company adopted in the first quarter of 2011. Adoption of this guidance did not have a material effect on the Company’s consolidated financial condition, results of operations or cash flows.

Recent Accounting Developments

In September 2011, the FASB issued ASU 2011-08 amending Codification topic 350 – Intangibles – Goodwill and Other. The amendment simplifies how goodwill is tested for impairment by permitting entities to first assess qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying value as a basis for determining whether it is necessary to perform the two step goodwill impairment test. The amendment is effective for the interim and annual goodwill impairment tests performed for fiscal years beginning after December 15, 2011. Early adoption is permitted, but the Company did not early adopt. Adoption of this guidance is not expected to have a material effect on the Company’s consolidated financial condition, results of operations or cash flows.

In June 2011, the FASB issued ASU 2011-05 amending Codification Topic 220—Comprehensive Income. The amendment requires that other comprehensive income be either presented in a single continuous statement or two separate but consecutive statements. In addition, the amendment requires the disclosure of reclassification adjustments for items reclassified from other comprehensive income to net income on the face of the financial statements. The amendment is effective for the interim and annual periods beginning after December 15, 2011 and should be applied retrospectively. This standard will only affect the Company’s presentation of comprehensive income and will not affect the Company’s financial position, results of operations, and cash flows.

In May 2011, the FASB issued ASU 2011-04 amending Codification Topic 820—Fair Value Measurements and Disclosures. The amendments were intended to result in common fair value measurement and disclosure requirements in U.S. GAAP and International Financial Reporting Standards (“IFRS”). The amendment expands and enhances current disclosures about fair value measurement and clarifies the FASB’s intent regarding the application of existing fair value measurement requirements in certain circumstances. The amendments are effective for the interim and annual periods beginning after December 15, 2011 and should be applied prospectively. We are currently evaluating the impact of this amendment on the Company’s consolidated financial position, results of operations and cash flows.

In October 2010, the FASB issued ASU 2010-26 amending Codification Topic 944 – Financial Services – Insurance; Accounting for Costs Associated with Acquiring or Renewing Insurance Contracts. The amendment clarifies which costs relating to the acquisition of new or renewal insurance contracts qualify for deferral. In addition, the amendment limits deferrable costs that can be capitalized to those that are incremental direct costs related to the successful acquisition of new or renewal insurance contracts. The amendment is effective for fiscal years and interim periods within a fiscal year, beginning after December 15, 2011. The guidance is to be applied prospectively upon effectiveness of the amendment, with retrospective application permitted, but not required. The Company did not early adopt. The Company will adopt this guidance prospectively in the first quarter of 2012. Adoption of this guidance is not expected to have a material effect on the Company’s consolidated financial condition, results of operations or cash flows.