Business Combinations (Goodwill) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Goodwill		$ 54,285	$ 36,609
Goodwill, Acquired During Period		20,233
Goodwill impairment	$ (3,200)	(3,183)	0	$ 0
Goodwill, Translation and Purchase Accounting Adjustments		626
Collins Aerospace Systems [Member]
Business Acquisition [Line Items]
Goodwill		31,571	35,025
Goodwill, Acquired During Period		(890)
Goodwill impairment	$ (3,200)	(3,183)
Goodwill, Translation and Purchase Accounting Adjustments		619
Pratt and Whitney [Member]
Business Acquisition [Line Items]
Goodwill		1,563	1,563
Goodwill, Acquired During Period		0
Goodwill impairment		0
Goodwill, Translation and Purchase Accounting Adjustments		0
Raytheon Intelligence & Space
Business Acquisition [Line Items]
Goodwill		9,240	0
Goodwill, Acquired During Period		9,236
Goodwill impairment		0
Goodwill, Translation and Purchase Accounting Adjustments		4
Raytheon Missiles & Defense
Business Acquisition [Line Items]
Goodwill		11,890	0
Goodwill, Acquired During Period		11,887
Goodwill impairment		0
Goodwill, Translation and Purchase Accounting Adjustments		3
Total Segments [Member]
Business Acquisition [Line Items]
Goodwill		54,264	36,588
Goodwill, Acquired During Period		20,233
Goodwill impairment		(3,183)
Goodwill, Translation and Purchase Accounting Adjustments		626
Eliminations and other [Member]
Business Acquisition [Line Items]
Goodwill		21	$ 21
Goodwill, Acquired During Period		0
Goodwill impairment		0
Goodwill, Translation and Purchase Accounting Adjustments		$ 0