Quarterly Operating Results (Unaudited) (Schedule of Quarterly Operating Results) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Selected Quarterly Financial Information [Abstract]
Net sales	$ 7,842	$ 7,446	$ 7,159	$ 6,729	$ 7,360	$ 6,806	$ 6,625	$ 6,267	$ 29,176	$ 27,058	$ 25,348
Gross margin	2,010	1,947	1,954	1,852	1,967	1,935	1,848	1,735
Income from continuing operations	879	861	813	775	828	641	790	624	3,342	2,910	2,022
Net income attributable to Raytheon Company	$ 885	$ 860	$ 817	$ 781	$ 832	$ 644	$ 800	$ 633	$ 3,343	$ 2,909	$ 2,024
Basic EPS from continuing operations attributable to Raytheon Company common stockholders	$ 3.17	$ 3.08	$ 2.92	$ 2.77	$ 2.93	$ 2.25	$ 2.78	$ 2.20	$ 11.93	$ 10.16	$ 6.95
Diluted EPS from continuing operations attributable to Raytheon Company common stockholders	3.16	3.08	2.92	2.77	2.93	2.25	2.78	2.20	11.92	10.15	6.94
Basic EPS attributable to Raytheon Company common stockholders	3.16	3.08	2.92	2.77	2.93	2.25	2.78	2.20	11.94	10.16	6.96
Diluted EPS attributable to Raytheon Company common stockholders	$ 3.16	$ 3.08	$ 2.92	$ 2.77	$ 2.93	$ 2.25	$ 2.78	$ 2.19	$ 11.93	$ 10.15	$ 6.95
Workdays	59 days	63 days	64 days	63 days	58 days	63 days	64 days	64 days
Net Periodic Benefit Cost (Credit), Loss Due to Settlement						$ 288