Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2017
Disclosure Text Block [Abstract]
Basis of Presentation	1. Basis of Presentation The Company American Express Company (the Company) is a global services company that provides customers with access to products, insights and experiences that enrich lives and build business success. The Company’s principal products and services are charge and credit payment card products and travel-related services offered to consumers and businesses around the world. Business travel-related services are offered through the non-consolidated joint venture, American Express Global Business Travel (the GBT JV). The Company’s various products and services are sold globally to diverse customer groups, including consumers, small businesses, mid-sized companies and large corporations. These products and services are sold through various channels, including direct mail, online applications, in-house and third-party sales forces and direct response advertising. The accompanying Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 (the Annual Report). If not materially different, certain footnote disclosures included therein have been omitted from this Quarterly Report on Form 10-Q. The interim consolidated financial information in this report has not been audited. In the opinion of management, all adjustments, which consist of normal recurring adjustments necessary for a fair statement of the interim period consolidated financial information, have been made. Results of operations reported for interim periods are not necessarily indicative of results for the entire year. 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. Certain reclassifications of prior period amounts have been made to conform to the current period presentation. Recently Issued Accounting Standards In May 2014, the Financial Accounting Standards Board (FASB) issued new accounting guidance on revenue recognition. The accounting standard establishes the principles to apply to determine the amount and timing of revenue recognition, specifying the accounting for certain costs related to revenue, and requiring additional disclosures about the nature, amount, timing and uncertainty of revenues and related cash flows. The guidance, as amended, supersedes most of the current revenue recognition requirements, and is effective January 1, 2018. Upon adoption of the new revenue recognition guidance, the Company anticipates using the full retrospective method, which applies the new standard to each prior reporting period presented. The Company has been working on the implementation of the standard since its issuance in 2014 and has made significant progress in evaluating the potential impact on its Consolidated Financial Statements. There will be changes to the recognition timing and classification of revenues and expenses; however, the Company does not expect a significant impact to pretax income upon adoption. The Company is also in the process of implementing changes to its accounting policies, business processes, systems and internal controls to support the recognition and disclosure requirements under the new standard. In January 2016, the FASB issued new accounting guidance on the recognition and measurement of financial assets and financial liabilities. The guidance, which is effective January 1, 2018, makes targeted changes to current GAAP, specifically to the classification and measurement of equity securities, and to certain disclosure requirements associated with the fair value of financial instruments. The Company continues to evaluate the impact this guidance will have on its financial position, results of operations and cash flows, and in preparation for the implementation, is evaluating the impact the guidance will have on its cost method investments, as well as the impact the standard will have on its accounting policies, business processes, systems and internal controls. In February 2016, the FASB issued new accounting guidance on leases. The guidance, which is effective January 1, 2019, with early adoption permitted, requires virtually all leases to be recognized on the Consolidated Balance Sheets. The Company currently anticipates adopting the standard effective January 1, 2019, using the modified retrospective approach, which requires recording existing operating leases on the Consolidated Balance Sheets upon adoption and in the comparative period. The Company is in the process of identifying changes to its accounting policies, business processes, systems, and internal controls in preparation for the implementation. Specifically, the Company is currently reviewing its lease portfolio and is evaluating and interpreting the requirements under the guidance, including the available accounting policy elections, in order to determine the impacts to the Company’s financial position, results of operations and cash flows upon adoption. In June 2016, the FASB issued new accounting guidance for recognition of credit losses on financial instruments, which is effective January 1, 2020, with early adoption permitted on January 1, 2019. The guidance introduces a new credit reserving model known as the Current Expected Credit Loss (CECL) model, which is based on expected losses, and differs significantly from the incurred loss approach used today. The CECL model requires measurement of expected credit losses not only based on historical experience and current conditions, but also by including reasonable and supportable forecasts incorporating forward-looking information and will likely result in earlier recognition of credit reserves. The Company does not intend to adopt the new standard early and is currently evaluating the impact the new guidance will have on its financial position, results of operations and cash flows; however, it is expected that the CECL model will alter the assumptions used in estimating credit losses on Card Member loans and receivables, among other financial instruments (e.g., investments in available-for-sale debt securities), and may result in material changes to the Company’s credit reserves.

1. Basis of Presentation

The Company

American Express Company (the Company) is a global services company that provides customers with access to products, insights and experiences that enrich lives and build business success. The Company’s principal products and services are charge and credit payment card products and travel-related services offered to consumers and businesses around the world. Business travel-related services are offered through the non-consolidated joint venture, American Express Global Business Travel (the GBT JV). The Company’s various products and services are sold globally to diverse customer groups, including consumers, small businesses, mid-sized companies and large corporations. These products and services are sold through various channels, including direct mail, online applications, in-house and third-party sales forces and direct response advertising.

The accompanying Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 (the Annual Report). If not materially different, certain footnote disclosures included therein have been omitted from this Quarterly Report on Form 10-Q.

The interim consolidated financial information in this report has not been audited. In the opinion of management, all adjustments, which consist of normal recurring adjustments necessary for a fair statement of the interim period consolidated financial information, have been made. Results of operations reported for interim periods are not necessarily indicative of results for the entire year.

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.

Certain reclassifications of prior period amounts have been made to conform to the current period presentation.

Recently Issued Accounting Standards

In May 2014, the Financial Accounting Standards Board (FASB) issued new accounting guidance on revenue recognition. The accounting standard establishes the principles to apply to determine the amount and timing of revenue recognition, specifying the accounting for certain costs related to revenue, and requiring additional disclosures about the nature, amount, timing and uncertainty of revenues and related cash flows. The guidance, as amended, supersedes most of the current revenue recognition requirements, and is effective January 1, 2018.

Upon adoption of the new revenue recognition guidance, the Company anticipates using the full retrospective method, which applies the new standard to each prior reporting period presented. The Company has been working on the implementation of the standard since its issuance in 2014 and has made significant progress in evaluating the potential impact on its Consolidated Financial Statements. There will be changes to the recognition timing and classification of revenues and expenses; however, the Company does not expect a significant impact to pretax income upon adoption. The Company is also in the process of implementing changes to its accounting policies, business processes, systems and internal controls to support the recognition and disclosure requirements under the new standard.

In January 2016, the FASB issued new accounting guidance on the recognition and measurement of financial assets and financial liabilities. The guidance, which is effective January 1, 2018, makes targeted changes to current GAAP, specifically to the classification and measurement of equity securities, and to certain disclosure requirements associated with the fair value of financial instruments. The Company continues to evaluate the impact this guidance will have on its financial position, results of operations and cash flows, and in preparation for the implementation, is evaluating the impact the guidance will have on its cost method investments, as well as the impact the standard will have on its accounting policies, business processes, systems and internal controls.

In February 2016, the FASB issued new accounting guidance on leases. The guidance, which is effective January 1, 2019, with early adoption permitted, requires virtually all leases to be recognized on the Consolidated Balance Sheets. The Company currently anticipates adopting the standard effective January 1, 2019, using the modified retrospective approach, which requires recording existing operating leases on the Consolidated Balance Sheets upon adoption and in the comparative period. The Company is in the process of identifying changes to its accounting policies, business processes, systems, and internal controls in preparation for the implementation. Specifically, the Company is currently reviewing its lease portfolio and is evaluating and interpreting the requirements under the guidance, including the available accounting policy elections, in order to determine the impacts to the Company’s financial position, results of operations and cash flows upon adoption.

In June 2016, the FASB issued new accounting guidance for recognition of credit losses on financial instruments, which is effective January 1, 2020, with early adoption permitted on January 1, 2019. The guidance introduces a new credit reserving model known as the Current Expected Credit Loss (CECL) model, which is based on expected losses, and differs significantly from the incurred loss approach used today. The CECL model requires measurement of expected credit losses not only based on historical experience and current conditions, but also by including reasonable and supportable forecasts incorporating forward-looking information and will likely result in earlier recognition of credit reserves. The Company does not intend to adopt the new standard early and is currently evaluating the impact the new guidance will have on its financial position, results of operations and cash flows; however, it is expected that the CECL model will alter the assumptions used in estimating credit losses on Card Member loans and receivables, among other financial instruments (e.g., investments in available-for-sale debt securities), and may result in material changes to the Company’s credit reserves.