Basis of Presentation (Policies)	9 Months Ended
Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The preparation of Consolidated Financial Statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosures of contingent assets and liabilities. These accounting estimates reflect the best judgment of management, but actual results could differ. Effective April 1, 2021, we prospectively changed the recognition of certain costs paid to a third party previously recognized over the twelve month card membership period in Net card fees in the Consolidated Statements of Income; such costs are now recorded as incurred in Marketing and business development expense. This change is not material to the Consolidated Financial Statements.
Recently Adopted Accounting Standards	Effective January 1, 2021, we elected to change our accounting for investments in qualified affordable housing projects from the equity method of accounting to the proportional amortization method (PAM) in accordance with the accounting guidance. PAM results in the amortization of the initial cost of the investment in proportion to the related tax credits, and recognition of the net investment performance in the statement of income as a component of Income tax provision, while the equity method reflected losses related to the investments as a component of Other, net expenses. As a result, we believe PAM is preferable as it better reflects the economics of our tax credit investments. Since the impact of this change is immaterial to our prior and current period financial statements, we implemented PAM on a prospective basis which resulted in a one-time charge to Income tax provision of $55 million in the first quarter of 2021, reflecting the cumulative impact of the difference in the timing of expense recognition between the equity method and PAM.
Impaired Loans and Receivables	Impaired loans and receivables are individual larger balance or homogeneous pools of smaller balance loans and receivables for which it is probable that we will be unable to collect all amounts due according to the original contractual terms of the customer agreement. We consider impaired loans and receivables to include (i) loans over 90 days past due still accruing interest, (ii) non-accrual loans and (iii) loans and receivables modified as troubled debt restructurings (TDRs). In instances where the customer is experiencing financial difficulty, we may modify, through various financial relief programs, loans and receivables with the intention to minimize losses and improve collectability, while providing customers with temporary or permanent financial relief. We have classified loans and receivables in these modification programs as TDRs and continue to classify customer accounts that have exited a modification program as a TDR, with such accounts identified as “Out of Program TDRs.”
Reserves for Credit Losses	Reserves for credit losses represent our best estimate of the expected credit losses in our outstanding portfolio of Card Member loans and receivables as of the balance sheet date. The CECL methodology requires us to estimate lifetime expected credit losses by incorporating historical loss experience, as well as current and future economic conditions over a reasonable and supportable period (R&S Period), which is approximately three years, beyond the balance sheet date. We make various judgments combined with historical loss experience to determine a reserve rate that is applied to the outstanding loan or receivable balance to produce a reserve for expected credit losses. We use a combination of statistically-based models that incorporate current and future economic conditions throughout the R&S Period. The process of estimating expected credit losses is based on several key models: Probability of Default (PD), Exposure at Default (EAD), and future recoveries for each month of the R&S Period. Beyond the R&S Period, we estimate expected credit losses by immediately reverting to long-term average loss rates. •PD models are used to estimate the likelihood an account will be written-off. •EAD models are used to estimate the balance of an account at the time of write-off. This includes balances less expected repayments based on historical payment and revolve behavior, which vary by customer. Due to the nature of revolving loan portfolios, the EAD models are complex and involve assumptions regarding the relationship between future spend and payment behaviors. •Recovery models are used to estimate amounts that are expected to be received from Card Members after default occurs, typically as a result of collection efforts. Future recoveries are estimated taking into consideration the time of default, time elapsed since default and macroeconomic conditions. We also estimate the likelihood and magnitude of recovery of previously written off accounts considering how long ago the account was written off and future economic conditions. Our models are developed using historical loss experience covering the economic cycle and consider the impact of account characteristics on expected losses. Future economic conditions that are incorporated over the R&S Period include multiple macroeconomic scenarios provided to us by an independent third party. Management reviews these economic scenarios and applies judgment to weight them in order to reflect the uncertainty surrounding these scenarios. These macroeconomic scenarios contain certain variables, including unemployment rates and real gross domestic product (GDP), that are significant to our models. We also evaluate whether to include qualitative reserves to cover losses that are expected but, in our assessment, may not be adequately represented in the quantitative methods or the economic assumptions. We consider whether to adjust the quantitative reserves (higher or lower) to address possible limitations within the models or factors not included within the models, such as external conditions, emerging portfolio trends, the nature and size of the portfolio, portfolio concentrations, the volume and severity of past due accounts, or management risk actions. Lifetime losses for most of our loans and receivables are evaluated at an appropriate level of granularity, including assessment on a pooled basis where financial assets share similar risk characteristics, such as past spend and remittance behaviors, credit bureau scores where available, delinquency status, tenure of balance outstanding, amongst others. Credit losses on accrued interest are measured and presented as part of Reserves for credit losses on the Consolidated Balance Sheets and within the Provisions for credit losses in the Consolidated Statements of Income, rather than reversing interest income. Separate models are used for accounts deemed a troubled debt restructuring, which are measured individually using a discounted cash flow model. Loans and receivable balances are written off when we consider amounts to be uncollectible, which is generally determined by the number of days past due and is typically no later than 180 days past due for pay in full or revolving loans and 120 days past due for term loans. Loans and receivables in bankruptcy or owed by deceased individuals are generally written off upon notification.
Investments	Investment securities principally include available-for-sale debt securities carried at fair value on the Consolidated Balance Sheets. Unrealized losses attributable to credit deterioration are recorded in the Consolidated Statements of Income in Other loans Provision for credit losses. Unrealized gains and any portion of a security’s unrealized loss attributable to non-credit losses are recorded in the Consolidated Statements of Comprehensive Income, net of tax. Investment securities also include equity securities carried at fair value on the Consolidated Balance Sheets with unrealized gains and losses recorded in the Consolidated Statements of Income as Other, net expense. Realized gains and losses are recognized upon disposition of the securities using the specific identification method.
Asset Securitizations	We periodically securitize Card Member loans and receivables arising from our card businesses through the transfer of those assets to securitization trusts, American Express Credit Account Master Trust (the Lending Trust) and American Express Issuance Trust II (the Charge Trust and together with the Lending Trust, the Trusts). The Trusts then issue debt securities collateralized by the transferred assets to third-party investors.The Trusts are considered VIEs as they have insufficient equity at risk to finance their activities, which are to issue debt securities that are collateralized by the underlying Card Member loans and receivables. We perform the servicing and key decision making for the Trusts, and therefore have the power to direct the activities that most significantly impact the Trusts’ economic performance, which are the collection of the underlying Card Member loans and receivables. In addition, we hold all of the variable interests in both Trusts, with the exception of the debt securities issued to third-party investors.These variable interests held by us provide us with the right to receive benefits and the obligation to absorb losses, which could be significant to both the Lending Trust and the Charge Trust. Based on these considerations, we are the primary beneficiary of the Trusts and therefore consolidate the Trusts.
Contingencies	We have accrued for certain of our outstanding legal proceedings. An accrual is recorded when it is both (a) probable that a loss has occurred and (b) the amount of loss can be reasonably estimated. There may be instances in which an exposure to loss exceeds the accrual. We evaluate, on a quarterly basis, developments in legal proceedings that could cause an increase or decrease in the amount of the accrual that has been previously recorded, or a revision to the disclosed estimated range of possible losses, as applicable. For those disclosed material legal proceedings where a loss is reasonably possible in future periods, whether in excess of a recorded accrual for legal or tax contingencies, or where there is no such accrual, and for which we are able to estimate a range of possible loss, the current estimated range is zero to $210 million in excess of any accruals related to those matters. This range represents management’s estimate based on currently available information and does not represent our maximum loss exposure; actual results may vary significantly. As such legal proceedings evolve, we may need to increase our range of possible loss or recorded accruals. In addition, it is possible that significantly increased merchant steering or other actions impairing the Card Member experience as a result of an adverse resolution in one or any combination of the disclosed merchant cases could have a material adverse effect on our business and results of operations. In addition, we face exposure associated with Card Member purchases, including with respect to the following: •Return Protection — refunds the price of qualifying purchases made with eligible cards, where the merchant will not accept the return, for up to 90 days from the date of purchase; and •Merchant Protection — protects Card Members primarily against non-delivery of purchases, usually in the event of the bankruptcy or liquidation of a merchant. When this occurs, the Card Member may dispute the transaction for which we will generally credit the Card Member’s account. If we are unable to collect the amount from the merchant, we may bear the loss for the amount credited to the Card Member. The largest component of the exposure relates to Card Member transactions associated with travel-related merchants, primarily through business arrangements where we have remitted payment to such merchants for a Card Member travel purchase that has not yet been used or “flown.”
Derivatives	A majority of our derivative assets and liabilities as of September 30, 2021 and December 31, 2020 are subject to master netting agreements with our derivative counterparties. Accordingly, where appropriate, we have elected to present derivative assets and liabilities with the same counterparty on a net basis in the Consolidated Balance Sheets.The changes in the fair value of derivatives that are not designated as hedges are intended to offset the related foreign exchange gains or losses of the underlying foreign currency exposures.
Fair Values	We have certain assets that are subject to measurement at fair value on a nonrecurring basis. For these assets, measurement at fair value in periods subsequent to their initial recognition is applicable if they are determined to be impaired or where there are observable price changes for equity investments without readily determinable fair values. During the nine months ended September 30, 2021 and the year ended December 31, 2020, we did not have any material assets that were measured at fair value due to impairment. We estimate the Level 3 fair value of equity investments without readily determinable fair values based on price changes as of the date of new similar equity financing transactions completed by the companies in our portfolio. The carrying value of equity investments without readily determinable fair values totaled $1.3 billion and $530 million as of September 30, 2021 and December 31, 2020, respectively. These amounts are included within Other assets on the Consolidated Balance Sheets. We recorded net unrealized gains of $103 million and $25 million for the three months ended September 30, 2021 and 2020, respectively, and $728 million and $47 million for the nine months ended September 30, 2021 and 2020, respectively. Unrealized losses including any impairments were not significant for any of the three and nine months ended September 30, 2021 and 2020. Beginning in January 2018, cumulative net unrealized gains for equity investments without readily determinable fair values totaled $1.1 billion and $347 million as of September 30, 2021 and December 31, 2020, respectively. In addition, we also have certain equity investments measured at fair value using the net asset value practical expedient. Such investments were immaterial as of both September 30, 2021 and December 31, 2020.
Guarantees	Our recognition of these instruments is at fair value. In addition, we establish reserves when a loss is probable and the amount can be reasonably estimated.

Basis of Presentation (Policies)

9 Months Ended

Sep. 30, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The preparation of Consolidated Financial Statements in conformity with accounting principles generally accepted in the United States of America (GAAP) requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and the disclosures of contingent assets and liabilities. These accounting estimates reflect the best judgment of management, but actual results could differ.

Effective April 1, 2021, we prospectively changed the recognition of certain costs paid to a third party previously recognized over the twelve month card membership period in Net card fees in the Consolidated Statements of Income; such costs are now recorded as incurred in Marketing and business development expense. This change is not material to the Consolidated Financial Statements.

Recently Adopted Accounting Standards

Effective January 1, 2021, we elected to change our accounting for investments in qualified affordable housing projects from the equity method of accounting to the proportional amortization method (PAM) in accordance with the accounting guidance. PAM results in the amortization of the initial cost of the investment in proportion to the related tax credits, and recognition of the net investment performance in the statement of income as a component of Income tax provision, while the equity method reflected losses related to the investments as a component of Other, net expenses. As a result, we believe PAM is preferable as it better reflects the economics of our tax credit investments. Since the impact of this change is immaterial to our prior and current period financial statements, we implemented PAM on a prospective basis which resulted in a one-time charge to Income tax provision of $55 million in the first quarter of 2021, reflecting the cumulative impact of the difference in the timing of expense recognition between the equity method and PAM.

Impaired Loans and Receivables

Impaired loans and receivables are individual larger balance or homogeneous pools of smaller balance loans and receivables for which it is probable that we will be unable to collect all amounts due according to the original contractual terms of the customer agreement. We consider impaired loans and receivables to include (i) loans over 90 days past due still accruing interest, (ii) non-accrual loans and (iii) loans and receivables modified as troubled debt restructurings (TDRs).

In instances where the customer is experiencing financial difficulty, we may modify, through various financial relief programs, loans and receivables with the intention to minimize losses and improve collectability, while providing customers with temporary or permanent financial relief. We have classified loans and receivables in these modification programs as TDRs and continue to classify customer accounts that have exited a modification program as a TDR, with such accounts identified as “Out of Program TDRs.”

Reserves for Credit Losses

Reserves for credit losses represent our best estimate of the expected credit losses in our outstanding portfolio of Card Member loans and receivables as of the balance sheet date. The CECL methodology requires us to estimate lifetime expected credit losses by incorporating historical loss experience, as well as current and future economic conditions over a reasonable and supportable period (R&S Period), which is approximately three years, beyond the balance sheet date. We make various judgments combined with historical loss experience to determine a reserve rate that is applied to the outstanding loan or receivable balance to produce a reserve for expected credit losses.

We use a combination of statistically-based models that incorporate current and future economic conditions throughout the R&S Period. The process of estimating expected credit losses is based on several key models: Probability of Default (PD), Exposure at Default (EAD), and future recoveries for each month of the R&S Period. Beyond the R&S Period, we estimate expected credit losses by immediately reverting to long-term average loss rates.

•PD models are used to estimate the likelihood an account will be written-off.

•EAD models are used to estimate the balance of an account at the time of write-off. This includes balances less expected repayments based on historical payment and revolve behavior, which vary by customer. Due to the nature of revolving loan portfolios, the EAD models are complex and involve assumptions regarding the relationship between future spend and payment behaviors.

•Recovery models are used to estimate amounts that are expected to be received from Card Members after default occurs, typically as a result of collection efforts. Future recoveries are estimated taking into consideration the time of default, time elapsed since default and macroeconomic conditions.

We also estimate the likelihood and magnitude of recovery of previously written off accounts considering how long ago the account was written off and future economic conditions. Our models are developed using historical loss experience covering the economic cycle and consider the impact of account characteristics on expected losses.

Future economic conditions that are incorporated over the R&S Period include multiple macroeconomic scenarios provided to us by an independent third party. Management reviews these economic scenarios and applies judgment to weight them in order to reflect the uncertainty surrounding these scenarios. These macroeconomic scenarios contain certain variables, including unemployment rates and real gross domestic product (GDP), that are significant to our models.

We also evaluate whether to include qualitative reserves to cover losses that are expected but, in our assessment, may not be adequately represented in the quantitative methods or the economic assumptions. We consider whether to adjust the quantitative reserves (higher or lower) to address possible limitations within the models or factors not included within the models, such as external conditions, emerging portfolio trends, the nature and size of the portfolio, portfolio concentrations, the volume and severity of past due accounts, or management risk actions.

Lifetime losses for most of our loans and receivables are evaluated at an appropriate level of granularity, including assessment on a pooled basis where financial assets share similar risk characteristics, such as past spend and remittance behaviors, credit bureau scores where available, delinquency status, tenure of balance outstanding, amongst others. Credit losses on accrued interest are measured and presented as part of Reserves for credit losses on the Consolidated Balance Sheets and within the Provisions for credit losses in the Consolidated Statements of Income, rather than reversing interest income. Separate models are used for accounts deemed a troubled debt restructuring, which are measured individually using a discounted cash flow model.

Loans and receivable balances are written off when we consider amounts to be uncollectible, which is generally determined by the number of days past due and is typically no later than 180 days past due for pay in full or revolving loans and 120 days past due for term loans. Loans and receivables in bankruptcy or owed by deceased individuals are generally written off upon notification.

Investments

Investment securities principally include available-for-sale debt securities carried at fair value on the Consolidated Balance Sheets. Unrealized losses attributable to credit deterioration are recorded in the Consolidated Statements of Income in Other loans Provision for credit losses. Unrealized gains and any portion of a security’s unrealized loss attributable to non-credit losses are recorded in the Consolidated Statements of Comprehensive Income, net of tax. Investment securities also include equity securities carried at fair value on the Consolidated Balance Sheets with unrealized gains and losses recorded in the Consolidated Statements of Income as Other, net expense. Realized gains and losses are recognized upon disposition of the securities using the specific identification method.

Asset Securitizations

We periodically securitize Card Member loans and receivables arising from our card businesses through the transfer of those assets to securitization trusts, American Express Credit Account Master Trust (the Lending Trust) and American Express Issuance Trust II (the Charge Trust and together with the Lending Trust, the Trusts). The Trusts then issue debt securities collateralized by the transferred assets to third-party investors.The Trusts are considered VIEs as they have insufficient equity at risk to finance their activities, which are to issue debt securities that are collateralized by the underlying Card Member loans and receivables. We perform the servicing and key decision making for the Trusts, and therefore have the power to direct the activities that most significantly impact the Trusts’ economic performance, which are the collection of the underlying Card Member loans and receivables. In addition, we hold all of the variable interests in both Trusts, with the exception of the debt securities issued to third-party investors.These variable interests held by us provide us with the right to receive benefits and the obligation to absorb losses, which could be significant to both the Lending Trust and the Charge Trust. Based on these considerations, we are the primary beneficiary of the Trusts and therefore consolidate the Trusts.

Contingencies

We have accrued for certain of our outstanding legal proceedings. An accrual is recorded when it is both (a) probable that a loss has occurred and (b) the amount of loss can be reasonably estimated. There may be instances in which an exposure to loss exceeds the accrual. We evaluate, on a quarterly basis, developments in legal proceedings that could cause an increase or decrease in the amount of the accrual that has been previously recorded, or a revision to the disclosed estimated range of possible losses, as applicable.

For those disclosed material legal proceedings where a loss is reasonably possible in future periods, whether in excess of a recorded accrual for legal or tax contingencies, or where there is no such accrual, and for which we are able to estimate a range of possible loss, the current estimated range is zero to $210 million in excess of any accruals related to those matters. This range represents management’s estimate based on currently available information and does not represent our maximum loss exposure; actual results may vary significantly. As such legal proceedings evolve, we may need to increase our range of possible loss or recorded accruals. In addition, it is possible that significantly increased merchant steering or other actions impairing the Card Member experience as a result of an adverse resolution in one or any combination of the disclosed merchant cases could have a material adverse effect on our business and results of operations.

In addition, we face exposure associated with Card Member purchases, including with respect to the following:

•Return Protection — refunds the price of qualifying purchases made with eligible cards, where the merchant will not accept the return, for up to 90 days from the date of purchase; and

•Merchant Protection — protects Card Members primarily against non-delivery of purchases, usually in the event of the bankruptcy or liquidation of a merchant. When this occurs, the Card Member may dispute the transaction for which we will generally credit the Card Member’s account. If we are unable to collect the amount from the merchant, we may bear the loss for the amount credited to the Card Member. The largest component of the exposure relates to Card Member transactions associated with travel-related merchants, primarily through business arrangements where we have remitted payment to such merchants for a Card Member travel purchase that has not yet been used or “flown.”

Derivatives

A majority of our derivative assets and liabilities as of September 30, 2021 and December 31, 2020 are subject to master netting agreements with our derivative counterparties. Accordingly, where appropriate, we have elected to present derivative assets and liabilities with the same counterparty on a net basis in the Consolidated Balance Sheets.The changes in the fair value of derivatives that are not designated as hedges are intended to offset the related foreign exchange gains or losses of the underlying foreign currency exposures.

Fair Values

We have certain assets that are subject to measurement at fair value on a nonrecurring basis. For these assets, measurement at fair value in periods subsequent to their initial recognition is applicable if they are determined to be impaired or where there are observable price changes for equity investments without readily determinable fair values. During the nine months ended September 30, 2021 and the year ended December 31, 2020, we did not have any material assets that were measured at fair value due to impairment.

We estimate the Level 3 fair value of equity investments without readily determinable fair values based on price changes as of the date of new similar equity financing transactions completed by the companies in our portfolio. The carrying value of equity investments without readily determinable fair values totaled $1.3 billion and $530 million as of September 30, 2021 and December 31, 2020, respectively. These amounts are included within Other assets on the Consolidated Balance Sheets. We recorded net unrealized gains of $103 million and $25 million for the three months ended September 30, 2021 and 2020, respectively, and $728 million and $47 million for the nine months ended September 30, 2021 and 2020, respectively. Unrealized losses including any impairments were not significant for any of the three and nine months ended September 30, 2021 and 2020. Beginning in January 2018, cumulative net unrealized gains for equity investments without readily determinable fair values totaled $1.1 billion and $347 million as of September 30, 2021 and December 31, 2020, respectively.

In addition, we also have certain equity investments measured at fair value using the net asset value practical expedient. Such investments were immaterial as of both September 30, 2021 and December 31, 2020.

Guarantees

Our recognition of these instruments is at fair value. In addition, we establish reserves when a loss is probable and the amount can be reasonably estimated.