Revenue Recognition - Current And Non-Current Air Traffic Liability (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Beginning balance	$ 661	$ 580
Increase (decrease) to air traffic liability - points redeemed	(182)	(391)
Increase (decrease) to air traffic liability - points earned and sold	254	472
Ending balance	$ 733	$ 661

Value of revenue deferred or cost to provide future products or services, primarily air transportation, associated with programs used by airlines to encourage passenger loyalty by providing rewards geared to the frequency of travel on the sponsoring airline, typically in the form of frequent flyer miles, points, or segments that can be accumulated and converted into free or discounted travel or other redemption options.

No definition available.

Name:	jblu_AirTrafficLiability
Namespace Prefix:	jblu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant