Other Assets (Narrative) (Details) - USD ($) $ in Millions	Jul. 12, 2018	Jun. 30, 2018	Dec. 31, 2017
Other Assets [Line Items]
Other assets, net of accumulated amortization		$ 1,800	$ 2,027
Sea Launch Receivables [Member]
Other Assets [Line Items]
Other assets, net of accumulated amortization		295	$ 356
Sea Launch Receivables [Member] | S.P. Koroley Rocket And Space Corporation Energia [Member]
Other Assets [Line Items]
Other assets, net of accumulated amortization		162
Sea Launch Receivables [Member] | PO Yuzhnoye Mashinostroitelny Zavod [Member]
Other Assets [Line Items]
Other assets, net of accumulated amortization		89
Sea Launch Receivables [Member] | KB Yuzhnoye [Member]
Other Assets [Line Items]
Other assets, net of accumulated amortization		$ 44
Subsequent Event [Member] | Spirit Aerosystems [Member]
Other Assets [Line Items]
Loss Contingency, Loss in Period	$ 137