Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of Delta Air Lines, Inc. and our consolidated subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States ("GAAP") for interim financial information. Consistent with these requirements, this Form 10-Q does not include all the information required by GAAP for complete financial statements. As a result, this Form 10-Q should be read in conjunction with the Consolidated Financial Statements and accompanying Notes in our Form 10-K for the year ended December 31, 2021. Management believes the accompanying unaudited Condensed Consolidated Financial Statements reflect all adjustments, including normal recurring items, considered necessary for a fair statement of results for the interim periods presented. Due to impacts from the COVID-19 pandemic and the ongoing recovery, seasonal variations in the demand for air travel, the volatility of aircraft fuel prices and other factors, operating results for the three and nine months ended September 30, 2022 are not necessarily indicative of operating results for the entire year. We reclassified certain prior period amounts to conform to the current period presentation. Unless otherwise noted, all amounts disclosed are stated before consideration of income taxes.
Recent Accounting Standards	Recent Accounting Standards Standards Effective in Future Years Fair Value of Equity Investments. In June 2022, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2022-03, "Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions." Under this standard, a contractual restriction on the sale of an equity security is not considered in measuring the security's fair value. The standard also requires certain disclosures for equity securities that are subject to contractual restrictions. The ASU becomes effective January 1, 2024. Upon adoption, we do not believe it will have a material impact on the valuation of our equity investments; however, we may be required to include additional disclosures to the extent we have material equity investments subject to contractual sale restrictions. Supplier Finance Program Obligations. In September 2022, the FASB issued ASU No. 2022-04, "Liabilities—Supplier Finance Programs (Subtopic 405-50)." This standard requires disclosure of the key terms of outstanding supplier finance programs and a rollforward of the related obligations. The new standard does not affect the recognition, measurement or financial statement presentation of supplier finance program obligations. The ASU becomes effective January 1, 2023, except for the rollforward requirement, which becomes effective January 1, 2024. Upon adoption, we may be required to include additional disclosures to the extent we have material supplier finance program obligations.
Cash Equivalents and Restricted Cash Equivalents	Cash Equivalents and Restricted Cash Equivalents. Cash equivalents generally consist of money market funds. Restricted cash equivalents generally consist of money market funds, time deposits, commercial paper and negotiable certificates of deposit, which primarily relate to certain self-insurance obligations and airport commitments as well as proceeds from debt issued to finance, among other things, a portion of the construction costs for our new terminal facilities at New York's LaGuardia Airport. Restricted cash equivalents are recorded in prepaid expenses and other and other noncurrent assets on our Consolidated Balance Sheet ("balance sheet"). The fair value of these cash equivalents is based on a market approach using prices generated by market transactions involving identical or comparable assets.
Short-Term and Long-Term Investments	Short-Term Investments. Short-term investments consist of U.S. government and agency securities. The fair values of these investments are based on a market approach using industry standard valuation techniques that incorporate observable inputs such as quoted market prices, interest rates, benchmark curves, credit ratings of the security and other observable information.Long-Term Investments. Our long-term investments measured at fair value primarily consist of equity investments, which are valued based on market prices or other observable transactions and inputs, and are recorded in equity investments on our balance sheet. Our equity investments in private companies are classified as Level 3 in the fair value hierarchy as their equity is not traded on a public exchange and our valuations incorporate certain unobservable inputs, including non-public equity issuances and forecasts provided by our investees. Fair value measurement using unobservable inputs is inherently uncertain, and a change in significant inputs could result in different fair values. See Note 4, "Investments," for further information on our equity investments.
Fuel Hedge Contracts	Fuel Hedge Contracts. Our derivative contracts to hedge the financial risk from changing fuel prices are primarily related to inventory at our wholly-owned subsidiary, Monroe Energy, LLC ("Monroe"). Our fuel hedge portfolio may consist of a combination of options, swaps or futures contracts, most of which have a duration of less than three months. Option and swap contracts are valued under income approaches using option pricing models and discounted cash flow models, respectively, based on data either readily observable in public markets, derived from public markets or provided by counterparties who regularly trade in public markets. Futures contracts and options on futures contracts are traded on a public exchange and valued based on quoted market prices.
Fair Value Investments	Fair Value Investments. Changes in the valuation of investments accounted for at fair value are recorded in gain/(loss) on investments, net in our income statement within non-operating expense and are driven by changes in stock prices, foreign currency fluctuations and other valuation techniques for investments in companies without publicly-traded shares.
Equity Method Investments	Equity Method Investments. We record our share of our equity method investees' financial results in our income statement

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The accompanying unaudited Condensed Consolidated Financial Statements include the accounts of Delta Air Lines, Inc. and our consolidated subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States ("GAAP") for interim financial information. Consistent with these requirements, this Form 10-Q does not include all the information required by GAAP for complete financial statements. As a result, this Form 10-Q should be read in conjunction with the Consolidated Financial Statements and accompanying Notes in our Form 10-K for the year ended December 31, 2021.

Management believes the accompanying unaudited Condensed Consolidated Financial Statements reflect all adjustments, including normal recurring items, considered necessary for a fair statement of results for the interim periods presented.

Due to impacts from the COVID-19 pandemic and the ongoing recovery, seasonal variations in the demand for air travel, the volatility of aircraft fuel prices and other factors, operating results for the three and nine months ended September 30, 2022 are not necessarily indicative of operating results for the entire year.

We reclassified certain prior period amounts to conform to the current period presentation. Unless otherwise noted, all amounts disclosed are stated before consideration of income taxes.

Recent Accounting Standards

Standards Effective in Future Years

Fair Value of Equity Investments. In June 2022, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") No. 2022-03, "Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions." Under this standard, a contractual restriction on the sale of an equity security is not considered in measuring the security's fair value. The standard also requires certain disclosures for equity securities that are subject to contractual restrictions. The ASU becomes effective January 1, 2024. Upon adoption, we do not believe it will have a material impact on the valuation of our equity investments; however, we may be required to include additional disclosures to the extent we have material equity investments subject to contractual sale restrictions.

Supplier Finance Program Obligations. In September 2022, the FASB issued ASU No. 2022-04, "Liabilities—Supplier Finance Programs (Subtopic 405-50)." This standard requires disclosure of the key terms of outstanding supplier finance programs and a rollforward of the related obligations. The new standard does not affect the recognition, measurement or financial statement presentation of supplier finance program obligations. The ASU becomes effective January 1, 2023, except for the rollforward requirement, which becomes effective January 1, 2024. Upon adoption, we may be required to include additional disclosures to the extent we have material supplier finance program obligations.

Cash Equivalents and Restricted Cash Equivalents

Cash Equivalents and Restricted Cash Equivalents. Cash equivalents generally consist of money market funds. Restricted cash equivalents generally consist of money market funds, time deposits, commercial paper and negotiable certificates of deposit, which primarily relate to certain self-insurance obligations and airport commitments as well as proceeds from debt issued to finance, among other things, a portion of the construction costs for our new terminal facilities at New York's LaGuardia Airport. Restricted cash equivalents are recorded in prepaid expenses and other and other noncurrent assets on our Consolidated Balance Sheet ("balance sheet"). The fair value of these cash equivalents is based on a market approach using prices generated by market transactions involving identical or comparable assets.

Short-Term and Long-Term Investments

Short-Term Investments. Short-term investments consist of U.S. government and agency securities. The fair values of these investments are based on a market approach using industry standard valuation techniques that incorporate observable inputs such as quoted market prices, interest rates, benchmark curves, credit ratings of the security and other observable information.Long-Term Investments. Our long-term investments measured at fair value primarily consist of equity investments, which are valued based on market prices or other observable transactions and inputs, and are recorded in equity investments on our balance sheet. Our equity investments in private companies are classified as Level 3 in the fair value hierarchy as their equity is not traded on a public exchange and our valuations incorporate certain unobservable inputs, including non-public equity issuances and forecasts provided by our investees. Fair value measurement using unobservable inputs is inherently uncertain, and a change in significant inputs could result in different fair values. See Note 4, "Investments," for further information on our equity investments.

Fuel Hedge Contracts

Fuel Hedge Contracts. Our derivative contracts to hedge the financial risk from changing fuel prices are primarily related to inventory at our wholly-owned subsidiary, Monroe Energy, LLC ("Monroe"). Our fuel hedge portfolio may consist of a combination of options, swaps or futures contracts, most of which have a duration of less than three months. Option and swap contracts are valued under income approaches using option pricing models and discounted cash flow models, respectively, based on data either readily observable in public markets, derived from public markets or provided by counterparties who regularly trade in public markets. Futures contracts and options on futures contracts are traded on a public exchange and valued based on quoted market prices.

Fair Value Investments

Fair Value Investments. Changes in the valuation of investments accounted for at fair value are recorded in gain/(loss) on investments, net in our income statement within non-operating expense and are driven by changes in stock prices, foreign currency fluctuations and other valuation techniques for investments in companies without publicly-traded shares.

Equity Method Investments

Equity Method Investments. We record our share of our equity method investees' financial results in our income statement