SHARE-BASED COMPENSATION - Recognized Non-Cash Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense included in operating expenses	$ 16,184	$ 15,149	$ 9,567
Income tax benefit	3,703	3,160	3,328
After-tax stock-based compensation expense	12,481	11,989	6,239
Station operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense included in operating expenses	4,673	6,855	1,694
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense included in operating expenses	$ 11,511	$ 8,294	$ 7,873

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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