| Document and Entity Information | Oct. 02, 2019 |
| Cover [Abstract] | |
| Entity Registrant Name | RAYTHEON CO/ |
| Amendment Flag | false |
| Entity Central Index Key | 0001047122 |
| Document Type | 8-K |
| Document Period End Date | Oct. 2, 2019 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 1-13699 |
| Entity Tax Identification Number | 95-1778500 |
| Entity Address, Address Line One | 870 Winter Street |
| Entity Address, City or Town | Waltham |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02451 |
| City Area Code | (781) |
| Local Phone Number | 522-3000 |
| Written Communications | true |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $0.01 par value |
| Trading Symbol | RTN |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
