| Document and Entity Information | May 07, 2020 |
| Document And Entity Information [Line Items] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001437107 |
| Document Type | 8-K |
| Document Period End Date | May 7, 2020 |
| Entity Registrant Name | Discovery, Inc. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-34177 |
| Entity Tax Identification Number | 35-2333914 |
| Entity Address, Address Line One | 8403 Colesville Road |
| Entity Address, City or Town | Silver Spring |
| Entity Address, State or Province | MD |
| Entity Address, Postal Zip Code | 20910 |
| City Area Code | 240 |
| Local Phone Number | 662-2000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Class A [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Series A Common Stock |
| Trading Symbol | DISCA |
| Security Exchange Name | NASDAQ |
| Common Class B [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Series B Common Stock |
| Trading Symbol | DISCB |
| Security Exchange Name | NASDAQ |
| Common Class C [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Series C Common Stock |
| Trading Symbol | DISCK |
| Security Exchange Name | NASDAQ |
