INFORMATION ON BUSINESS SEGMENTS - Total Assets For Each Business Segment (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total assets	$ 47,684	$ 44,876
Business segments
Segment Reporting Information [Line Items]
Total assets	39,853	37,230
Business segments | Aeronautics
Segment Reporting Information [Line Items]
Total assets	9,469	8,435
Business segments | Missiles and Fire Control
Segment Reporting Information [Line Items]
Total assets	5,678	5,017
Business segments | Rotary and Mission Systems
Segment Reporting Information [Line Items]
Total assets	18,914	18,333
Business segments | Space
Segment Reporting Information [Line Items]
Total assets	5,792	5,445
Corporate
Segment Reporting Information [Line Items]
Total assets	$ 7,831	$ 7,646