CONDENSED CONSOLIDATING FINANCIAL STATEMENTS (Narrative) (Details) $ in Millions	Sep. 30, 2018 USD ($)
Debt Instrument [Line Items]
Consolidated total debt	$ 3,902.3
Sinclair Television Group, Inc.
Debt Instrument [Line Items]
Consolidated total debt	3,881.2
Consolidated total debt, guaranteed	$ 3,838.3
Sinclair Television Group, Inc. \| 5.375% Senior Unsecured Notes due 2021
Debt Instrument [Line Items]
Interest rate	5.375%
Sinclair Television Group, Inc. \| 5.625% Senior Unsecured Notes, due 2024
Debt Instrument [Line Items]
Interest rate	5.625%
Sinclair Television Group, Inc. \| 6.125% Senior Unsecured Notes due 2022
Debt Instrument [Line Items]
Interest rate	6.125%
Sinclair Television Group, Inc. \| 5.875% Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Interest rate	5.875%
Sinclair Television Group, Inc. \| 5.125% Senior Unsecured Notes due 2027
Debt Instrument [Line Items]
Interest rate	5.125%
Sinclair Broadcast Group, Inc. \| 5.375% Senior Unsecured Notes due 2021
Debt Instrument [Line Items]
Interest rate	5.375%
Sinclair Broadcast Group, Inc. \| 5.625% Senior Unsecured Notes, due 2024
Debt Instrument [Line Items]
Interest rate	5.625%
Sinclair Broadcast Group, Inc. \| 6.125% Senior Unsecured Notes due 2022
Debt Instrument [Line Items]
Interest rate	6.125%
Sinclair Broadcast Group, Inc. \| 5.875% Senior Unsecured Notes due 2026
Debt Instrument [Line Items]
Interest rate	5.875%
Sinclair Broadcast Group, Inc. \| 5.125% Senior Unsecured Notes due 2027
Debt Instrument [Line Items]
Interest rate	5.125%

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