Commitments And Contingencies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) agreement employee	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Commitments and Contingencies [Line Items]
Total expense under operating leases	$ 380	$ 309	$ 307
Letters of credit	$ 1,700
Number of company-negotiated labor agreements | agreement	94
Number of collective agreements expected to be renegotiated | agreement	21
Number of employees covered by expected renegotiated collective agreements | employee	5,500
Gross amount of assets under capital leases	$ 485	19
Accumulated amortization of assets under capital lease	5,055	4,720
Assets Held under Capital Leases
Commitments and Contingencies [Line Items]
Accumulated amortization of assets under capital lease	$ 61	$ 3
Unionized Employees Concentration Risk
Commitments and Contingencies [Line Items]
Percent of employees represented by labor organizations	20.00%
Maximum | Aerospace
Commitments and Contingencies [Line Items]
Period preceding delivery of aircraft to customer fair market value of trade-in aircraft is established, days, maximum	45 days