Earnings per share - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Net income attributable to TEGNA Inc.	$ 86,308	$ 73,979
Weighted average number of common shares outstanding - basic (in shares)	218,277	216,709
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Weighted average number of common shares outstanding - diluted (in shares)	218,863	217,202
Net income per share – basic (in dollars per share)	$ 0.40	$ 0.34
Net income per share – diluted (in dollars per share)	$ 0.39	$ 0.34
Restricted stock units
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	284	179
Performance shares
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	298	256
Stock options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Effect of dilutive securities (in shares)	4	58