CONDENSED CONSOLIDATING FINANCIAL STATEMENTS - Narrative (Details) $ in Millions	Sep. 30, 2020 USD ($)
Debt Instrument [Line Items]
Consolidated total debt	$ 12,463
Subsidiary Issuer
Debt Instrument [Line Items]
Consolidated total debt	4,415
Amount of debt guaranteed by parent	$ 4,375
5.375% Senior Unsecured Notes due 2021 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.375%
5.375% Senior Unsecured Notes due 2021 \| Guarantor Subsidiaries and KDSM, LLC \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.375%
5.625% Senior Unsecured Notes Due 2021 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.625%
6.125% Senior Unsecured Notes due 2022 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	6.125%
6.125% Senior Unsecured Notes due 2022 \| Guarantor Subsidiaries and KDSM, LLC \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	6.125%
5.875% Senior Unsecured Notes due 2026 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.875%
5.875% Senior Unsecured Notes due 2026 \| Guarantor Subsidiaries and KDSM, LLC \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.875%
5.125% Senior Unsecured Notes due 2027 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.125%
5.125% Senior Unsecured Notes due 2027 \| Guarantor Subsidiaries and KDSM, LLC \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.125%
5.500% Senior Unsecured Notes due 2030 \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%
5.500% Senior Unsecured Notes due 2030 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%
5.500% Senior Unsecured Notes due 2030 \| Guarantor Subsidiaries and KDSM, LLC \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%
5.625% Senior Unsecured Notes due 2024 \| Sinclair Television Group, Inc. \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.625%
5.625% Senior Unsecured Notes due 2024 \| Guarantor Subsidiaries and KDSM, LLC \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.625%

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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