CONDENSED CONSOLIDATING FINANCIAL STATEMENTS - Narrative (Details) $ in Millions	Jun. 30, 2021 USD ($)
Debt Instrument [Line Items]
Consolidated total debt	$ 12,539
Subsidiary Issuer
Debt Instrument [Line Items]
Consolidated total debt	4,395
Amount of debt guaranteed by parent	$ 4,358
5.875% Senior Unsecured Notes due 2026 \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.875%
5.875% Senior Unsecured Notes due 2026 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.875%
5.125% Senior Unsecured Notes due 2027 \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.125%
5.125% Senior Unsecured Notes due 2027 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.125%
5.500% Senior Unsecured Notes \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%
5.500% Senior Unsecured Notes \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%
4.125% Senior Secured Notes due 2030 \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	4.125%

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Contractual interest rate for funds borrowed, under the debt agreement.

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