Note 10 - Commitments and Contingencies (Details Textual) $ in Millions	Sep. 30, 2020 USD ($)
Acquisition and Investments Commitments	$ 80

The amount of commitments related to acquisition and investments.

No definition available.

Name:	gtn_AcquisitionAndInvestmentsCommitments
Namespace Prefix:	gtn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant