| Document and Entity Information | Jul. 22, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | TEGNA INC |
| Amendment Flag | false |
| Entity Central Index Key | 0000039899 |
| Document Type | 8-K |
| Document Period End Date | Jul. 22, 2021 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 1-6961 |
| Entity Tax Identification Number | 16-0442930 |
| Entity Address, Address Line One | 8350 Broad Street |
| Entity Address, Address Line Two | Suite 2000 |
| Entity Address, City or Town | Tysons |
| Entity Address, State or Province | VA |
| Entity Address, Postal Zip Code | 22102-5151 |
| City Area Code | (703) |
| Local Phone Number | 873-6600 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock |
| Trading Symbol | TGNA |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
