Note 3 - Acquisitions and Divestitures - Unaudited Pro Forma Results (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Raycom [Member]
Revenue (less agency commissions)	$ 2,139	$ 2,212
Net income	241	286
Net income attributable to common stockholders	$ 189	$ 234
Basic net income per share (in dollars per share)	$ 2.43	$ 3.25
Diluted net income per share (in dollars per share)	$ 2.41	$ 3.21
Revenue (less agency commissions)	$ 2,139	$ 2,212
Net income	$ 241	$ 286
Basic net income per share (in dollars per share)	$ 2.43	$ 3.25
Diluted net income per share (in dollars per share)	$ 2.41	$ 3.21
2017 Acquisitions [Member]
Revenue (less agency commissions)			$ 895
Net income			$ 261
Basic net income per share (in dollars per share)			$ 3.57
Diluted net income per share (in dollars per share)			$ 3.53
Revenue (less agency commissions)			$ 895
Net income			$ 261
Basic net income per share (in dollars per share)			$ 3.57
Diluted net income per share (in dollars per share)			$ 3.53