Airport Redevelopment	12 Months Ended
Airport Redevelopment	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Airport Redevelopment	AIRPORT REDEVELOPMENT New York-JFK Airport In 2015, we completed two phases of redevelopment at New York-JFK's Terminal 4 to facilitate convenient connections for our passengers and improve coordination with our SkyTeam alliance partners. Terminal 4 is operated by JFK International Air Terminal LLC ("IAT"), a private party, under its lease with the Port Authority of New York and New Jersey ("Port Authority"). In December 2010, we entered into a 33-year agreement with IAT ("Sublease") to sublease space in Terminal 4. Also, in 2010, the Port Authority issued approximately $800 million principal amount of special project bonds (the "Series 8 Bonds") to fund the majority of the project. In December 2020, the NYTDC issued approximately $611 million principal amount of special project bonds to refinance the outstanding balance of the Series 8 Bonds. We have recognized a ROU asset and lease liability representing the fixed component of the lease payments for this facility. We have an equity method investment in JFK IAT Member LLC, which owns IAT, our sublessor at Terminal 4. The Sublease requires us to pay certain fixed management fees. We determined the investment is a variable interest entity and assessed whether we have a controlling financial interest in IAT. Our rights under the Sublease, with respect to management of Terminal 4, are consistent with rights granted to an anchor tenant under a standard airport lease. Accordingly, we do not consolidate this entity in our Consolidated Financial Statements. We continue to plan for further expansion of Terminal 4, however changes in the JFK market due to the COVID-19 pandemic have caused us to reevaluate our original plan to expand the terminal by 16 gates. We are working with the Port Authority and IAT to evaluate our options and determine the optimal size, scope and phasing of the expansion. Los Angeles International Airport ("LAX") We executed a modified lease agreement during 2016 with the City of Los Angeles (the "City"), which owns and operates LAX, and announced plans to modernize, upgrade and provide post-security connection to Terminals 2 and 3. Construction is underway, which includes a new centralized ticketing and arrival hall, a new security checkpoint, core infrastructure to support the City's planned airport people mover, ramp improvements and a post-security connector to the north side of the Tom Bradley International Terminal. Given reduced passenger volumes resulting from the COVID-19 pandemic, we have accelerated the construction schedule for this project. Additionally, in 2020, we enhanced the project’s scope to include a more customer-friendly design of Terminal 3, a Delta One lounge and expanded Delta Sky Club, and baggage system upgrades designed to increase the terminals’ operational efficiency going forward. Construction is expected to be completed by 2023. The project is expected to cost approximately $2.3 billion. A substantial majority of the project costs are being funded through the Regional Airports Improvement Corporation ("RAIC"), a California public benefit corporation, using an $800 million revolving credit facility provided by a group of lenders. The credit facility was executed during 2017 and amended in 2020, and we have guaranteed the obligations of the RAIC under the credit facility. Loans made under the credit facility are being repaid with the proceeds from the City’s purchase of completed project assets. Under the lease agreement and subsequent project component approvals by the City's Board of Airport Commissioners, the City has appropriated to date approximately $1.8 billion to purchase completed project assets, representing the maximum allowable reimbursement by the City. Costs incurred in excess of the $1.8 billion maximum will not be reimbursed by the City. We currently expect our net project costs to be approximately $500 million, of which approximately $200 million has been reflected as investing activities in our cash flows statement since the project started in 2017. In 2020, $315 million was spent on this project, with $293 million paid by the credit facility and $22 million paid directly by Delta. Based on our assessment of the project, we concluded that we do not control the underlying assets being constructed, and therefore, we do not have the project asset or related obligation recorded on our balance sheet. New York-LaGuardia Airport As part of the terminal redevelopment project at LaGuardia Airport, we are partnering with the Port Authority to replace Terminals C and D with a new state-of-the-art terminal facility consisting of 37 gates across four concourses connected to a central headhouse. The terminal will feature a new, larger Delta Sky Club, wider concourses, more gate seating and 75 percent more concessions space than the existing terminals. The facility will also offer direct access between the parking garage and terminal and improved roadways and drop-off/pick-up areas. The design of the new terminal will integrate sustainable technologies and improvements in energy efficiency. Construction will be phased to limit passenger inconvenience and is expected to be completed by 2026. In connection with the redevelopment, during 2017, we entered into an amended and restated terminal lease with the Port Authority with a term through 2050. Pursuant to the lease agreement, as amended to date, we will (1) fund (through debt issuance and existing cash) and undertake the design, management and construction of the terminal and certain off-premises supporting facilities, (2) receive a Port Authority contribution of $481 million to facilitate construction of the terminal and other supporting infrastructure, (3) be responsible for all operations and maintenance during the term of the lease and (4) have preferential rights to all gates in the terminal subject to Port Authority requirements with respect to accommodation of designated carriers. We currently expect our net project cost to be approximately $3.5 billion and we bear the risks of project construction, including any potential cost over-runs. Using funding primarily provided by existing financing arrangements, we spent approximately $600 million during 2020, bringing the total amount spent on the project to date to approximately $1.5 billion. See Note 8, "Debt," for additional information on the debt related to this redevelopment project, NYTDC Special Facilities Revenue Bonds, Series 2018 and NYTDC Special Facilities Revenue Bonds, Series 2020. In 2019, we opened Concourse G, the first of the four new concourses housing seven of the 37 new gates. Not only did it deliver the first direct impact to the Delta passenger experience, it also represented the first major phasing milestone. The next major milestone will be the opening of the headhouse and Concourse E, which is scheduled for 2022. As we are funding the majority of the LaGuardia redevelopment project, we account for the related assets as leasehold improvements. We entered into loan agreements to fund a portion of the construction, which are recorded on our balance sheet as debt with the proceeds reflected as restricted cash.