Segment Information (Unaudited) (Details 3) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenue, Contract Type [Line Items]
Sales	$ 8,189	$ 6,735
Concentration Risk, Percentage	100.00%	100.00%
Cost-type [Member]
Revenue, Contract Type [Line Items]
Sales	$ 4,076	$ 3,618
Concentration Risk, Percentage	50.00%	54.00%
Cost-type [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 2,002	$ 1,902
Concentration Risk, Percentage	58.00%	59.00%
Cost-type [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 408	$ 0
Concentration Risk, Percentage	30.00%	0.00%
Cost-type [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,274	$ 1,279
Concentration Risk, Percentage	50.00%	49.00%
Cost-type [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	$ 392	$ 437
Concentration Risk, Percentage	49.00%	48.00%
Fixed-price [Member]
Revenue, Contract Type [Line Items]
Sales	$ 4,113	$ 3,117
Concentration Risk, Percentage	50.00%	46.00%
Fixed-price [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,448	$ 1,319
Concentration Risk, Percentage	42.00%	41.00%
Fixed-price [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 968	$ 0
Concentration Risk, Percentage	70.00%	0.00%
Fixed-price [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,294	$ 1,320
Concentration Risk, Percentage	50.00%	51.00%
Fixed-price [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	$ 403	$ 478
Concentration Risk, Percentage	51.00%	52.00%
Intersegment Eliminations [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 46	$ 59
Intersegment Eliminations [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	62	0
Intersegment Eliminations [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	318	284
Intersegment Eliminations [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	182	229
Operating Segments [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 3,496	$ 3,280
Concentration Risk, Percentage	100.00%	100.00%
Operating Segments [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,438	$ 0
Concentration Risk, Percentage	100.00%	0.00%
Operating Segments [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 2,886	$ 2,883
Concentration Risk, Percentage	100.00%	100.00%
Operating Segments [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	$ 977	$ 1,144
Concentration Risk, Percentage	100.00%	100.00%