Summary of Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	Nature of Operations: Marsh & McLennan Companies, Inc. (the "Company”), a global professional services firm, is organized based on the different services that it offers. Under this organizational structure, the Company’s two business segments are Risk and Insurance Services and Consulting. The Risk and Insurance Services segment provides risk management activities and insurance broking, reinsurance broking and insurance program management services for businesses, public entities, insurance companies, associations, professional services organizations, and private clients. The Company conducts business in this segment through Marsh and Guy Carpenter. The Company conducts business in its Consulting segment through two main business groups. Mercer provides consulting expertise, advice, services and solutions in the areas of health, retirement, talent and investments. Oliver Wyman Group provides specialized management and economic and brand consulting services.
Principles of Consolidation	Principles of Consolidation: The accompanying consolidated financial statements include all wholly-owned and majority-owned subsidiaries. All significant inter-company transactions and balances have been eliminated.
Fiduciary Assets And Liabilities	Fiduciary Assets and Liabilities: In its capacity as an insurance broker or agent, the Company generally collects premiums from insureds and, after deducting its commissions, remits the premiums to the respective insurance underwriters. The Company also collects claims or refunds from underwriters on behalf of insureds. Unremitted insurance premiums and claims proceeds are held by the Company in a fiduciary capacity. Risk and Insurance Services revenue includes interest on fiduciary funds of $27 million, $39 million and $47 million in 2013, 2012 and 2011, respectively. The Consulting segment recorded fiduciary interest income of $5 million in 2013 and $4 million in both 2012 and 2011. Since fiduciary assets are not available for corporate use, they are shown in the consolidated balance sheets as an offset to fiduciary liabilities. Net uncollected premiums and claims and the related payables amounted to $8.2 billion and $9.1 billion at December 31, 2013 and 2012, respectively. The Company is not a principal to the contracts under which the right to receive premiums or the right to receive reimbursement of insured losses arises. Net uncollected premiums and claims and the related payables are, therefore, not assets and liabilities of the Company and are not included in the accompanying consolidated balance sheets. In certain instances, the Company advances premiums, refunds or claims to insurance underwriters or insureds prior to collection. These advances are made from corporate funds and are reflected in the accompanying consolidated balance sheets as receivables. Mercer manages approximately $16 billion of assets in trusts or funds for which Mercer’s management or trustee fee is considered a variable interest. Mercer is not the primary beneficiary of these trusts or funds. Mercer’s only variable interest in any of these trusts or funds is its unpaid fees, if any. Mercer’s maximum exposure to loss of its interests is, therefore, limited to collection of its fees.
Revenue	Revenue: Risk and Insurance Services revenue includes insurance commissions, fees for services rendered and interest income on certain fiduciary funds. Insurance commissions and fees for risk transfer services generally are recorded as of the effective date of the applicable policies or, in certain cases (primarily in the Company's reinsurance broking operations), as of the effective date or billing date, whichever is later. A reserve for policy cancellation is provided based on historic and current data on cancellations. Fees for non-risk transfer services provided to clients are recognized over the period in which the services are provided, using a proportional performance model. Fees resulting from achievement of certain performance thresholds are recorded when such levels are attained and such fees are not subject to forfeiture. Consulting revenue includes fees paid by clients for advice and services and commissions from insurance companies for the placement of individual and group contracts. Fee revenue for engagements where remuneration is based on time plus out-of-pocket expenses is recognized based on the amount of time consulting professionals expend on the engagement. For fixed fee engagements, revenue is recognized using a proportional performance model. Revenue from insurance commissions not subject to a fee arrangement is recorded over the effective period of the applicable policies. Revenue for asset based fees is recognized on an accrual basis by applying the daily/monthly rate as contractually agreed with the client to the applicable net asset value. On a limited number of engagements, performance fees may also be earned for achieving certain prescribed performance criteria. Such fees are recognized when the performance criteria have been achieved and agreed to by the client. Reimbursable expenses incurred by professional staff in the generation of revenue and sub-advisory fees related to investment management are included in revenue and the related expenses are included in other operating expenses.
Cash and Cash Equivalents	Cash and Cash Equivalents: Cash and cash equivalents primarily consist of certificates of deposit and time deposits, with original maturities of three months or less, and money market funds. The estimated fair value of the Company's cash and cash equivalents approximates their carrying value. The Company is required to maintain operating funds of approximately $190 million related to regulatory requirements outside the U.S. or as collateral under captive insurance arrangements.
Fixed Assets	Fixed Assets: Fixed assets are stated at cost less accumulated depreciation and amortization. Expenditures for improvements are capitalized. Upon sale or retirement, the cost and related accumulated depreciation and amortization are removed from the accounts and any gain or loss is reflected in income. Expenditures for maintenance and repairs are charged to operations as incurred. Depreciation of buildings, building improvements, furniture, and equipment is provided on a straight-line basis over the estimated useful lives of these assets. Furniture and equipment is depreciated over periods ranging from three to ten years. Leasehold improvements are amortized on a straight-line basis over the periods covered by the applicable leases or the estimated useful life of the improvement, whichever is less. Buildings are depreciated over periods ranging from thirty to forty years. The Company periodically reviews long-lived assets for impairment whenever events or changes indicate that the carrying value of assets may not be recoverable.
Investments	Investments: The Company holds investments primarily in private companies and certain private equity funds. Certain investments, primarily investments in private equity funds, are accounted for under the equity method using a consistently applied three-month lag period adjusted for any known significant changes from the lag period to the reporting date of the Company. The underlying private equity funds follow investment company accounting, where investments within the fund are carried at fair value. The Company records in earnings, investment gains/losses for its proportionate share of the change in fair value of the funds, which amounted to gains of $12 million, $33 million and $10 million in 2013, 2012 and 2011, respectively. Investments recorded using the equity method are included in other assets in the consolidated balance sheets. As part of the sale of MMC Capital in 2005, the Company retained the right to receive certain performance fees related to the Trident II and Trident III private equity partnerships. The Company recognizes performance fee income when such fees are no longer subject to forfeiture, which may take a number of years to resolve. The Company deferred the recognition of income related to such performance fees of $38 million and $63 million at December 31, 2013 and 2012, respectively, related to Trident III. This income is based on the investment performance over the life of each investment in the private equity fund, and future declines in fund performance from current levels may result in the forfeiture of such revenue. Trident II has now fully harvested all its portfolio investments and final distributions were made to partners during the fourth quarter of 2013. Therefore, the Company no longer holds an investment in Trident II. Approximately $40 million and $15 million of performance fees were recognized in 2013 related to Trident III and Trident II, respectively, and included as part of investment income. The Company received approximately $100 million in cash proceeds related to Trident II partnership distributions in 2013. Gains or losses recognized in earnings from the investments, including the performance fees discussed above, are included in investment income in the consolidated statements of income.
Goodwill and Intangible Assets	Goodwill and Other Intangible Assets: Goodwill represents acquisition costs in excess of the fair value of net assets acquired. Goodwill is reviewed at least annually for impairment. The Company performs an annual impairment test for each of its reporting units during the third quarter of each year. When a step 1 test is performed, fair values of the reporting units are estimated using either a market approach or a discounted cash flow model. Carrying values for the reporting units are based on balances at the prior quarter end and include directly identified assets and liabilities as well as an allocation of those assets and liabilities not recorded at the reporting unit level. As discussed in Note 6, the Company may elect to assess qualitative factors to determine if a step 1 assessment is necessary. Other intangible assets, which primarily consist of customer lists, that are not deemed to have an indefinite life are amortized over their estimated lives and reviewed for impairment upon the occurrence of certain triggering events in accordance with applicable accounting literature.
Capitalized Software Costs	Capitalized Software Costs: The Company capitalizes certain costs to develop, purchase or modify software for the internal use of the Company. These costs are amortized on a straight-line basis over periods ranging from 3 to 10 years. Costs incurred during the preliminary project stage and post implementation stage, are expensed as incurred. Costs incurred during the application development stage are capitalized. Costs related to updates and enhancements are only capitalized if they will result in additional functionality. Capitalized computer software costs of $399 million and $278 million, net of accumulated amortization of $748 million and $691 million at December 31, 2013 and 2012, respectively, are included in other assets in the consolidated balance sheets.
Legal and Other Loss Contingencies	Legal and Other Loss Contingencies: The Company and its subsidiaries are subject to a significant number of claims, lawsuits and proceedings including claims for errors and omissions ("E&O"). GAAP requires that a liability be recorded when a loss is both probable and reasonably estimable. Significant management judgment is required to apply this guidance. The Company utilizes case level reviews by inside and outside counsel, an internal actuarial analysis and other analysis to estimate potential losses. The liability is reviewed quarterly and adjusted as developments warrant. In many cases, the Company has not recorded a liability, other than for legal fees to defend the claim, because we are unable, at the present time, to make a determination that a loss is both probable and reasonably estimable. Given the unpredictability of E&O claims and of litigation that could flow from them, it is possible that an adverse outcome in a particular matter could have a material adverse effect on the Company’s businesses, results of operations, financial condition or cash flow in a given quarterly or annual period. In addition, to the extent that insurance coverage is available, significant management judgment is required to determine the amount of recoveries that are probable of collection under the Company’s various insurance programs. The legal and other contingent liabilities described above are not discounted.
Income Taxes	Income Taxes: The Company's effective tax rate reflects its income, statutory tax rates and tax planning in the various jurisdictions in which it operates. Significant judgment is required in determining the annual effective tax rate and in evaluating uncertain tax positions and the ability to realize deferred tax assets. The Company reports a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. The evaluation of a tax position is a two-step process. The first step involves recognition. The Company determines whether it is more likely than not that a tax position will be sustained upon tax examination, including resolution of any related appeals or litigation, based on only the technical merits of the position. The technical merits of a tax position derive from both statutory and judicial authority (legislation and statutes, legislative intent, regulations, rulings, and case law) and their applicability to the facts and circumstances of the tax position. If a tax position does not meet the more likely than not recognition threshold, the benefit of that position is not recognized in the financial statements. The second step is measurement. A tax position that meets the more likely than not recognition threshold is measured to determine the amount of benefit to recognize in the financial statements. The tax position is measured as the largest amount of benefit that is greater than 50 percent likely of being realized upon ultimate resolution with a taxing authority. Uncertain tax positions are evaluated based upon the facts and circumstances that exist at each reporting period. Subsequent changes in judgment based upon new information may lead to changes in recognition, de-recognition, and measurement. Adjustments may result, for example, upon resolution of an issue with the taxing authorities, or expiration of a statute of limitations barring an assessment for an issue. The Company recognizes interest and penalties, if any, related to unrecognized tax benefits in income tax expense. Tax law requires items be included in the Company's tax returns at different times than the items are reflected in the financial statements. As a result, the annual tax expense reflected in the consolidated statements of income is different than that reported in the income tax returns. Some of these differences are permanent, such as expenses that are not deductible in the returns, and some differences are temporary and reverse over time, such as depreciation expense. Temporary differences create deferred tax assets and liabilities. Deferred tax assets generally represent items that can be used as a tax deduction or credit in tax returns in future years for which benefit has already been recorded in the financial statements. Valuation allowances are established for deferred tax assets when it is estimated that future taxable income will be insufficient to use a deduction or credit in that jurisdiction. Deferred tax liabilities generally represent tax expense recognized in the financial statements for which payment has been deferred, or expense for which a deduction has been taken already in the tax return but the expense has not yet been recognized in the financial statements.
Derivative Instruments	Derivative Instruments: All derivatives, whether designated in hedging relationships or not, are recorded on the balance sheet at fair value. If the derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized in earnings. If the derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are recorded in other comprehensive income and are recognized in the income statement when the hedged item affects earnings. Changes in the fair value attributable to the ineffective portion of cash flow hedges are recognized in earnings.
Concentrations Of Credit Risk	Concentrations of Credit Risk: Financial instruments which potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, commissions and fees receivable and insurance recoverables. The Company maintains a policy providing for the diversification of cash and cash equivalent investments and places its investments in a large number of high quality financial institutions to limit the amount of credit risk exposure. Concentrations of credit risk with respect to receivables are generally limited due to the large number of clients and markets in which the Company does business, as well as the dispersion across many geographic areas.
Per Share Data	Per Share Data: From 2009 through 2012, the Company used the two-class method to compute basic and diluted earnings per share ("EPS"). Under the accounting guidance which applies to the calculation of EPS for share-based payment awards with rights to dividends or dividend equivalents, unvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are participating securities and should be included in the computation of basic and dilutive EPS using the two-class method. In the first quarter of 2013, the share-based payment awards with non-forfeitable rights to dividends became fully vested. As a result, the Company is no longer required to use the two-class method and in the first quarter of 2013 used the treasury stock method to calculate EPS. There was no difference in the earnings per share calculations when comparing the two-class method to the treasury stock method for the years ended 2012 and 2011. Therefore, the prior period information in the chart below shows the earnings per share calculation using the treasury stock method, consistent with current year presentation. Basic net income per share attributable to the Company and income from continuing operations per share are calculated by dividing the respective after-tax income attributable to common shares by the weighted average number of outstanding shares of the Company’s common stock. Diluted net income per share attributable to the Company and income from continuing operations per share are calculated by dividing the respective after-tax income attributable to common shares by the weighted average number of outstanding shares of the Company’s common stock, which have been adjusted for the dilutive effect of potentially issuable common shares.
Estimates	Estimates: The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results may vary from those estimates.
New Accounting Pronouncements	New Accounting Pronouncements: In July 2013, the FASB issued new accounting guidance related to the presentation of unrecognized tax benefits as a reduction to a deferred tax asset for a net operating loss carry-forward, a similar tax loss, or a tax credit carry-forward. However, to the extent a net operating loss carry-forward, a similar tax loss, or a tax credit carry-forward is not available at the reporting date under the tax law of the applicable jurisdiction to settle taxes that would result from the disallowance of the tax position or the entity does not intend to use the deferred tax asset for this purpose (provided that the tax law permits a choice), the unrecognized tax benefit shall be presented in the financial statement as a liability and shall not be combined with deferred tax assets. The guidance is effective for fiscal years beginning after December 15, 2013. The adoption of this new guidance will affect balance sheet classification and footnote disclosure only and is not expected to have a material impact on the Company's financial statements. In June 2013, the FASB issued new accounting guidance which amends the criteria for an entity to qualify as an investment company. The guidance clarifies the characteristics of an investment company, provides comprehensive guidance to determine whether an entity is an investment company and sets measurement and disclosure requirements for investment companies. The guidance is effective for interim and annual reporting periods beginning after December 15, 2013. Earlier application is prohibited. Adoption of the guidance is not expected to materially affect the Company's financial position, results of operations or cash flows. In February 2013, the FASB issued new accounting guidance that adds new disclosure requirements for items reclassified out of accumulated other comprehensive income. The Company implemented this new guidance for the reporting period ended March 31, 2013. Other than enhanced disclosure, the adoption of this new guidance did not have a material effect on the Company's financial statements. In the first quarter of 2012, the Company adopted new accounting guidance related to the presentation of Comprehensive Income. The new guidance gives an entity the option to present the total of comprehensive income, the components of net income, and the components of other comprehensive income either in a single continuous statement of comprehensive income or in two separate but consecutive statements. In both choices, an entity is required to present each component of net income along with total net income, each component of other comprehensive income along with a total for other comprehensive income, and a total amount for comprehensive income. The guidance eliminates the option to present the components of other comprehensive income as part of the statement of changes in stockholders’ equity. The guidance did not change the items that must be reported in other comprehensive income or when an item of other comprehensive income must be reclassified to net income. Other than enhanced disclosure, adoption of this new guidance did not have a material effect on the Company's financial statements. In January 2012, the Company adopted guidance issued by the FASB on accounting and disclosure requirements related to fair value measurements. The guidance expands the disclosures on Level 3 inputs by requiring quantitative disclosure of the unobservable inputs and assumptions, as well as description of the valuation processes, the sensitivity of the fair value to changes in unobservable inputs and the hierarchy classification, valuation techniques, and inputs for assets and liabilities whose fair value is only disclosed in the footnotes. Reclassifications: Certain reclassifications have been made to prior period amounts to conform with current year presentation, in particular with regard to the Per Share Data disclosure in Footnote 1, which is presented using the treasury stock method, since there is no difference in the earnings per share calculation between the treasury stock method and the two-class method for the three years presented.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2013

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of Operations: Marsh & McLennan Companies, Inc. (the "Company”), a global professional services firm, is organized based on the different services that it offers. Under this organizational structure, the Company’s two business segments are Risk and Insurance Services and Consulting.

The Risk and Insurance Services segment provides risk management activities and insurance broking, reinsurance broking and insurance program management services for businesses, public entities, insurance companies, associations, professional services organizations, and private clients. The Company conducts business in this segment through Marsh and Guy Carpenter.

The Company conducts business in its Consulting segment through two main business groups. Mercer provides consulting expertise, advice, services and solutions in the areas of health, retirement, talent and investments. Oliver Wyman Group provides specialized management and economic and brand consulting services.

Principles of Consolidation

Principles of Consolidation: The accompanying consolidated financial statements include all wholly-owned and majority-owned subsidiaries. All significant inter-company transactions and balances have been eliminated.

Fiduciary Assets And Liabilities

Fiduciary Assets and Liabilities: In its capacity as an insurance broker or agent, the Company generally collects premiums from insureds and, after deducting its commissions, remits the premiums to the respective insurance underwriters. The Company also collects claims or refunds from underwriters on behalf of insureds. Unremitted insurance premiums and claims proceeds are held by the Company in a fiduciary capacity. Risk and Insurance Services revenue includes interest on fiduciary funds of $27 million, $39 million and $47 million in 2013, 2012 and 2011, respectively. The Consulting segment recorded fiduciary interest income of $5 million in 2013 and $4 million in both 2012 and 2011. Since fiduciary assets are not available for corporate use, they are shown in the consolidated balance sheets as an offset to fiduciary liabilities.

Net uncollected premiums and claims and the related payables amounted to $8.2 billion and $9.1 billion at December 31, 2013 and 2012, respectively. The Company is not a principal to the contracts under which the right to receive premiums or the right to receive reimbursement of insured losses arises. Net uncollected premiums and claims and the related payables are, therefore, not assets and liabilities of the Company and are not included in the accompanying consolidated balance sheets.

In certain instances, the Company advances premiums, refunds or claims to insurance underwriters or insureds prior to collection. These advances are made from corporate funds and are reflected in the accompanying consolidated balance sheets as receivables.

Mercer manages approximately $16 billion of assets in trusts or funds for which Mercer’s management or trustee fee is considered a variable interest. Mercer is not the primary beneficiary of these trusts or funds. Mercer’s only variable interest in any of these trusts or funds is its unpaid fees, if any. Mercer’s maximum exposure to loss of its interests is, therefore, limited to collection of its fees.

Revenue

Revenue: Risk and Insurance Services revenue includes insurance commissions, fees for services rendered and interest income on certain fiduciary funds. Insurance commissions and fees for risk transfer services generally are recorded as of the effective date of the applicable policies or, in certain cases (primarily in the Company's reinsurance broking operations), as of the effective date or billing date, whichever is later. A reserve for policy cancellation is provided based on historic and current data on cancellations. Fees for non-risk transfer services provided to clients are recognized over the period in which the services are provided, using a proportional performance model. Fees resulting from achievement of certain performance thresholds are recorded when such levels are attained and such fees are not subject to forfeiture.

Consulting revenue includes fees paid by clients for advice and services and commissions from insurance companies for the placement of individual and group contracts. Fee revenue for engagements where remuneration is based on time plus out-of-pocket expenses is recognized based on the amount of time consulting professionals expend on the engagement. For fixed fee engagements, revenue is recognized using a proportional performance model. Revenue from insurance commissions not subject to a fee arrangement is recorded over the effective period of the applicable policies. Revenue for asset based fees is recognized on an accrual basis by applying the daily/monthly rate as contractually agreed with the client to the applicable net asset value. On a limited number of engagements, performance fees may also be earned for achieving certain prescribed performance criteria. Such fees are recognized when the performance criteria have been achieved and agreed to by the client. Reimbursable expenses incurred by professional staff in the generation of revenue and sub-advisory fees related to investment management are included in revenue and the related expenses are included in other operating expenses.

Cash and Cash Equivalents

Cash and Cash Equivalents: Cash and cash equivalents primarily consist of certificates of deposit and time deposits, with original maturities of three months or less, and money market funds. The estimated fair value of the Company's cash and cash equivalents approximates their carrying value. The Company is required to maintain operating funds of approximately $190 million related to regulatory requirements outside the U.S. or as collateral under captive insurance arrangements.

Fixed Assets

Fixed Assets: Fixed assets are stated at cost less accumulated depreciation and amortization. Expenditures for improvements are capitalized. Upon sale or retirement, the cost and related accumulated depreciation and amortization are removed from the accounts and any gain or loss is reflected in income. Expenditures for maintenance and repairs are charged to operations as incurred.

Depreciation of buildings, building improvements, furniture, and equipment is provided on a straight-line basis over the estimated useful lives of these assets. Furniture and equipment is depreciated over periods ranging from three to ten years. Leasehold improvements are amortized on a straight-line basis over the periods covered by the applicable leases or the estimated useful life of the improvement, whichever is less. Buildings are depreciated over periods ranging from thirty to forty years. The Company periodically reviews long-lived assets for impairment whenever events or changes indicate that the carrying value of assets may not be recoverable.

Investments

Investments: The Company holds investments primarily in private companies and certain private equity funds.

Certain investments, primarily investments in private equity funds, are accounted for under the equity method using a consistently applied three-month lag period adjusted for any known significant changes from the lag period to the reporting date of the Company. The underlying private equity funds follow investment company accounting, where investments within the fund are carried at fair value. The Company records in earnings, investment gains/losses for its proportionate share of the change in fair value of the funds, which amounted to gains of $12 million, $33 million and $10 million in 2013, 2012 and 2011, respectively. Investments recorded using the equity method are included in other assets in the consolidated balance sheets.

As part of the sale of MMC Capital in 2005, the Company retained the right to receive certain performance fees related to the Trident II and Trident III private equity partnerships. The Company recognizes performance fee income when such fees are no longer subject to forfeiture, which may take a number of years to resolve. The Company deferred the recognition of income related to such performance fees of $38 million and $63 million at December 31, 2013 and 2012, respectively, related to Trident III. This income is based on the investment performance over the life of each investment in the private equity fund, and future declines in fund performance from current levels may result in the forfeiture of such revenue. Trident II has now fully harvested all its portfolio investments and final distributions were made to partners during the fourth quarter of 2013. Therefore, the Company no longer holds an investment in Trident II. Approximately $40 million and $15 million of performance fees were recognized in 2013 related to Trident III and Trident II, respectively, and included as part of investment income. The Company received approximately $100 million in cash proceeds related to Trident II partnership distributions in 2013.

Gains or losses recognized in earnings from the investments, including the performance fees discussed above, are included in investment income in the consolidated statements of income.

Goodwill and Intangible Assets

Goodwill and Other Intangible Assets: Goodwill represents acquisition costs in excess of the fair value of net assets acquired. Goodwill is reviewed at least annually for impairment. The Company performs an annual impairment test for each of its reporting units during the third quarter of each year. When a step 1 test is performed, fair values of the reporting units are estimated using either a market approach or a discounted cash flow model. Carrying values for the reporting units are based on balances at the prior quarter end and include directly identified assets and liabilities as well as an allocation of those assets and liabilities not recorded at the reporting unit level. As discussed in Note 6, the Company may elect to assess qualitative factors to determine if a step 1 assessment is necessary. Other intangible assets, which primarily consist of customer lists, that are not deemed to have an indefinite life are amortized over their estimated lives and reviewed for impairment upon the occurrence of certain triggering events in accordance with applicable accounting literature.

Capitalized Software Costs

Capitalized Software Costs: The Company capitalizes certain costs to develop, purchase or modify software for the internal use of the Company. These costs are amortized on a straight-line basis over periods ranging from 3 to 10 years. Costs incurred during the preliminary project stage and post implementation stage, are expensed as incurred. Costs incurred during the application development stage are capitalized. Costs related to updates and enhancements are only capitalized if they will result in additional functionality. Capitalized computer software costs of $399 million and $278 million, net of accumulated amortization of $748 million and $691 million at December 31, 2013 and 2012, respectively, are included in other assets in the consolidated balance sheets.

Legal and Other Loss Contingencies

Legal and Other Loss Contingencies: The Company and its subsidiaries are subject to a significant number of claims, lawsuits and proceedings including claims for errors and omissions ("E&O"). GAAP requires that a liability be recorded when a loss is both probable and reasonably estimable. Significant management judgment is required to apply this guidance. The Company utilizes case level reviews by inside and outside counsel, an internal actuarial analysis and other analysis to estimate potential losses. The liability is reviewed quarterly and adjusted as developments warrant. In many cases, the Company has not recorded a liability, other than for legal fees to defend the claim, because we are unable, at the present time, to make a determination that a loss is both probable and reasonably estimable. Given the unpredictability of E&O claims and of litigation that could flow from them, it is possible that an adverse outcome in a particular matter could have a material adverse effect on the Company’s businesses, results of operations, financial condition or cash flow in a given quarterly or annual period.

In addition, to the extent that insurance coverage is available, significant management judgment is required to determine the amount of recoveries that are probable of collection under the Company’s various insurance programs.

The legal and other contingent liabilities described above are not discounted.

Income Taxes

Income Taxes: The Company's effective tax rate reflects its income, statutory tax rates and tax planning in the various jurisdictions in which it operates. Significant judgment is required in determining the annual effective tax rate and in evaluating uncertain tax positions and the ability to realize deferred tax assets.

The Company reports a liability for unrecognized tax benefits resulting from uncertain tax positions taken or expected to be taken in a tax return. The evaluation of a tax position is a two-step process. The first step involves recognition. The Company determines whether it is more likely than not that a tax position will be sustained upon tax examination, including resolution of any related appeals or litigation, based on only the technical merits of the position. The technical merits of a tax position derive from both statutory and judicial authority (legislation and statutes, legislative intent, regulations, rulings, and case law) and their applicability to the facts and circumstances of the tax position. If a tax position does not meet the more likely than not recognition threshold, the benefit of that position is not recognized in the financial statements. The second step is measurement. A tax position that meets the more likely than not recognition threshold is measured to determine the amount of benefit to recognize in the financial statements. The tax position is measured as the largest amount of benefit that is greater than 50 percent likely of being realized upon ultimate resolution with a taxing authority.

Uncertain tax positions are evaluated based upon the facts and circumstances that exist at each reporting period. Subsequent changes in judgment based upon new information may lead to changes in recognition, de-recognition, and measurement. Adjustments may result, for example, upon resolution of an issue with the taxing authorities, or expiration of a statute of limitations barring an assessment for an issue. The Company recognizes interest and penalties, if any, related to unrecognized tax benefits in income tax expense.

Tax law requires items be included in the Company's tax returns at different times than the items are reflected in the financial statements. As a result, the annual tax expense reflected in the consolidated statements of income is different than that reported in the income tax returns. Some of these differences are permanent, such as expenses that are not deductible in the returns, and some differences are temporary and reverse over time, such as depreciation expense. Temporary differences create deferred tax assets and liabilities. Deferred tax assets generally represent items that can be used as a tax deduction or credit in tax returns in future years for which benefit has already been recorded in the financial statements. Valuation allowances are established for deferred tax assets when it is estimated that future taxable income will be insufficient to use a deduction or credit in that jurisdiction. Deferred tax liabilities generally represent tax expense recognized in the financial statements for which payment has been deferred, or expense for which a deduction has been taken already in the tax return but the expense has not yet been recognized in the financial statements.

Derivative Instruments

Derivative Instruments: All derivatives, whether designated in hedging relationships or not, are recorded on the balance sheet at fair value. If the derivative is designated as a fair value hedge, the changes in the fair value of the derivative and of the hedged item attributable to the hedged risk are recognized in earnings. If the derivative is designated as a cash flow hedge, the effective portions of changes in the fair value of the derivative are recorded in other comprehensive income and are recognized in the income statement when the hedged item affects earnings. Changes in the fair value attributable to the ineffective portion of cash flow hedges are recognized in earnings.

Concentrations Of Credit Risk

Concentrations of Credit Risk: Financial instruments which potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents, commissions and fees receivable and insurance recoverables. The Company maintains a policy providing for the diversification of cash and cash equivalent investments and places its investments in a large number of high quality financial institutions to limit the amount of credit risk exposure. Concentrations of credit risk with respect to receivables are generally limited due to the large number of clients and markets in which the Company does business, as well as the dispersion across many geographic areas.

Per Share Data

Per Share Data: From 2009 through 2012, the Company used the two-class method to compute basic and diluted earnings per share ("EPS"). Under the accounting guidance which applies to the calculation of EPS for share-based payment awards with rights to dividends or dividend equivalents, unvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid) are participating securities and should be included in the computation of basic and dilutive EPS using the two-class method.

In the first quarter of 2013, the share-based payment awards with non-forfeitable rights to dividends became fully vested. As a result, the Company is no longer required to use the two-class method and in the first quarter of 2013 used the treasury stock method to calculate EPS. There was no difference in the earnings per share calculations when comparing the two-class method to the treasury stock method for the years ended 2012 and 2011. Therefore, the prior period information in the chart below shows the earnings per share calculation using the treasury stock method, consistent with current year presentation.

Basic net income per share attributable to the Company and income from continuing operations per share are calculated by dividing the respective after-tax income attributable to common shares by the weighted average number of outstanding shares of the Company’s common stock.

Diluted net income per share attributable to the Company and income from continuing operations per share are calculated by dividing the respective after-tax income attributable to common shares by the weighted average number of outstanding shares of the Company’s common stock, which have been adjusted for the dilutive effect of potentially issuable common shares.

Estimates

Estimates: The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results may vary from those estimates.

New Accounting Pronouncements

New Accounting Pronouncements: In July 2013, the FASB issued new accounting guidance related to the presentation of unrecognized tax benefits as a reduction to a deferred tax asset for a net operating loss carry-forward, a similar tax loss, or a tax credit carry-forward. However, to the extent a net operating loss carry-forward, a similar tax loss, or a tax credit carry-forward is not available at the reporting date under the tax law of the applicable jurisdiction to settle taxes that would result from the disallowance of the tax position or the entity does not intend to use the deferred tax asset for this purpose (provided that the tax law permits a choice), the unrecognized tax benefit shall be presented in the financial statement as a liability and shall not be combined with deferred tax assets. The guidance is effective for fiscal years beginning after December 15, 2013. The adoption of this new guidance will affect balance sheet classification and footnote disclosure only and is not expected to have a material impact on the Company's financial statements.

In June 2013, the FASB issued new accounting guidance which amends the criteria for an entity to qualify as an investment company. The guidance clarifies the characteristics of an investment company, provides comprehensive guidance to determine whether an entity is an investment company and sets

measurement and disclosure requirements for investment companies. The guidance is effective for interim and annual reporting periods beginning after December 15, 2013. Earlier application is prohibited. Adoption of the guidance is not expected to materially affect the Company's financial position, results of operations or cash flows.

In February 2013, the FASB issued new accounting guidance that adds new disclosure requirements for items reclassified out of accumulated other comprehensive income. The Company implemented this new guidance for the reporting period ended March 31, 2013. Other than enhanced disclosure, the adoption of this new guidance did not have a material effect on the Company's financial statements.

In the first quarter of 2012, the Company adopted new accounting guidance related to the presentation of Comprehensive Income. The new guidance gives an entity the option to present the total of comprehensive income, the components of net income, and the components of other comprehensive income either in a single continuous statement of comprehensive income or in two separate but consecutive statements. In both choices, an entity is required to present each component of net income along with total net income, each component of other comprehensive income along with a total for other comprehensive income, and a total amount for comprehensive income. The guidance eliminates the option to present the components of other comprehensive income as part of the statement of changes in stockholders’ equity. The guidance did not change the items that must be reported in other comprehensive income or when an item of other comprehensive income must be reclassified to net income. Other than enhanced disclosure, adoption of this new guidance did not have a material effect on the Company's financial statements.

In January 2012, the Company adopted guidance issued by the FASB on accounting and disclosure requirements related to fair value measurements. The guidance expands the disclosures on Level 3 inputs by requiring quantitative disclosure of the unobservable inputs and assumptions, as well as description of the valuation processes, the sensitivity of the fair value to changes in unobservable inputs and the hierarchy classification, valuation techniques, and inputs for assets and liabilities whose fair value is only disclosed in the footnotes.

Reclassifications: Certain reclassifications have been made to prior period amounts to conform with current year presentation, in particular with regard to the Per Share Data disclosure in Footnote 1, which is presented using the treasury stock method, since there is no difference in the earnings per share calculation between the treasury stock method and the two-class method for the three years presented.