Basis of Presentation (Unaudited) (Details 3) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Change in Contract with Customer, Asset and Liability [Abstract]
Unbilled receivables, net	$ 5,272		$ 5,272		$ 3,465
Amount of increase (decrease) in Unbilled Receivables			$ 1,807
Percent increase (decrease) in Unbilled Receivables			52.00%
Advance payments and amounts in excess of costs incurred	(1,711)		$ (1,711)		(1,761)
Amount of decrease (increase) in Customer Advances			$ 50
Percent decrease (increase) in Customer Advances			(3.00%)
Net contract assets (liabilities)	3,561		$ 3,561		$ 1,704
Amount of increase (decrease) in net contract assets (liabilities)			$ 1,857
Percent increase (decrease) in net contract assets (liabilities)			109.00%
Innovation Systems net contract assets	1,100		$ 1,100
Change in Contract with Customer, Liability [Abstract]
Contract with Customer, Liability, Revenue Recognized	$ 364	$ 272	$ 1,100	$ 850