| Document and Entity Information Document | Sep. 19, 2019 |
| Cover page. | |
| Document Type | 8-K |
| Document Period End Date | Sep. 19, 2019 |
| Entity Registrant Name | TEGNA INC. |
| Entity Central Index Key | 0000039899 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 1-6961 |
| Entity Tax Identification Number | 16-0442930 |
| Entity Address, Address Line One | 8350 Broad Street, 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 |
| Title of 12(b) Security | Common Stock |
| Trading Symbol | TGNA |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
