| Cover Page | Jul. 02, 2020 | Apr. 09, 2020 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Document Period End Date | Jul. 2, 2020 | |
| Entity Registrant Name | REALTY INCOME CORPORATION | |
| Entity Central Index Key | 0000726728 | |
| Amendment Flag | false | |
| Entity Incorporation, State or Country Code | MD | |
| Entity File Number | 1-13374 | |
| Entity Tax Identification Number | 33-0580106 | |
| Entity Address, Address Line One | 11995 El Camino Real | |
| Entity Address, City or Town | San Diego | |
| Entity Address, State or Province | CA | |
| Entity Address, Postal Zip Code | 92130 | |
| City Area Code | 858 | |
| Local Phone Number | 284-5000 | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Title of 12(b) Security | Common Stock, $0.01 Par Value | |
| Trading Symbol | O | |
| Security Exchange Name | NYSE | |
| Entity Emerging Growth Company | false |
