Restructuring Charges (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Severance charges	$ 0	$ 99	$ 102
Sikorsky Aircraft Corporation
Restructuring Cost and Reserve [Line Items]
Severance payments		40
Aeronautics
Restructuring Cost and Reserve [Line Items]
Severance charges		$ 80
Rotary and Mission Systems & Information System and Global Solutions
Restructuring Cost and Reserve [Line Items]
Severance charges			82
RMS
Restructuring Cost and Reserve [Line Items]
Severance charges			67
Information Systems & Global Solutions
Restructuring Cost and Reserve [Line Items]
Severance charges			$ 15