CONDENSED CONSOLIDATING FINANCIAL STATEMENTS - Statement of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
NET CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES	$ 100,943	$ 69,642
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Acquisition of property and equipment	(22,219)	(20,774)
Acquisition of businesses, net of cash acquired	0	(8,000)
Proceeds from the sale of assets	49	195,149
Investments in equity and cost method investees	(7,750)	(3,080)
Distributions from equity and cost method investees	10,832	3,272
Other, net	1,862	8,408
Net cash flows (used in) from investing activities	(20,950)	158,159
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable and commercial bank financing	363	163,089
Repayments of notes payable, commercial bank financing and capital leases	(16,950)	(284,422)
Net proceeds from the sale of Class A Common Stock	0	487,883
Dividends paid on Class A and Class B Common Stock	(18,392)	(16,257)
Increase (decrease) in intercompany payables	0	0
Other, net	(2,659)	(17,884)
Net cash flows (used in) from financing activities	(37,638)	332,409
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	42,355	560,210
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of period	995,940	260,184
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of period	1,038,295	820,394
Reportable legal entities \| Sinclair Broadcast Group, Inc.
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
NET CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES	1,304	1,126
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Acquisition of property and equipment	0	(50)
Acquisition of businesses, net of cash acquired		0
Proceeds from the sale of assets	0	0
Investments in equity and cost method investees	(370)	(945)
Distributions from equity and cost method investees	1,709	2,266
Other, net	0	0
Net cash flows (used in) from investing activities	1,339	1,271
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable and commercial bank financing	0	0
Repayments of notes payable, commercial bank financing and capital leases	0	0
Net proceeds from the sale of Class A Common Stock		487,883
Dividends paid on Class A and Class B Common Stock	(18,392)	(16,257)
Increase (decrease) in intercompany payables	14,869	(471,945)
Other, net	880	(2,078)
Net cash flows (used in) from financing activities	(2,643)	(2,397)
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	0	0
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of period	0	0
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of period	0	0
Reportable legal entities \| Sinclair Television Group, Inc.
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
NET CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES	(88,587)	(44,685)
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Acquisition of property and equipment	(2,214)	(3,259)
Acquisition of businesses, net of cash acquired		0
Proceeds from the sale of assets	0	0
Investments in equity and cost method investees	(31)	(300)
Distributions from equity and cost method investees	0	0
Other, net	1,862	3,083
Net cash flows (used in) from investing activities	(4,107)	(6,642)
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable and commercial bank financing	0	159,669
Repayments of notes payable, commercial bank financing and capital leases	(13,800)	(172,519)
Net proceeds from the sale of Class A Common Stock		0
Dividends paid on Class A and Class B Common Stock	0	0
Increase (decrease) in intercompany payables	251,594	615,437
Other, net	0	(360)
Net cash flows (used in) from financing activities	237,794	602,227
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	145,100	550,900
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of period	645,830	232,297
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of period	790,930	783,197
Reportable legal entities \| Guarantor Subsidiaries and KDSM, LLC
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
NET CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES	193,725	127,520
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Acquisition of property and equipment	(18,505)	(16,840)
Acquisition of businesses, net of cash acquired		(8,000)
Proceeds from the sale of assets	49	0
Investments in equity and cost method investees	(6,778)	(47)
Distributions from equity and cost method investees	0	0
Other, net	0	(357)
Net cash flows (used in) from investing activities	(25,234)	(24,530)
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable and commercial bank financing	0	0
Repayments of notes payable, commercial bank financing and capital leases	(843)	(445)
Net proceeds from the sale of Class A Common Stock		0
Dividends paid on Class A and Class B Common Stock	0	0
Increase (decrease) in intercompany payables	(256,169)	(102,763)
Other, net	0	586
Net cash flows (used in) from financing activities	(257,012)	(102,622)
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	(88,521)	368
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of period	323,383	10,875
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of period	234,862	11,243
Reportable legal entities \| Non- Guarantor Subsidiaries
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
NET CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES	(10,684)	(13,853)
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Acquisition of property and equipment	(1,500)	(806)
Acquisition of businesses, net of cash acquired		0
Proceeds from the sale of assets	0	195,149
Investments in equity and cost method investees	(571)	(1,788)
Distributions from equity and cost method investees	9,123	1,006
Other, net	0	5,682
Net cash flows (used in) from investing activities	7,052	187,879
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable and commercial bank financing	363	3,420
Repayments of notes payable, commercial bank financing and capital leases	(2,400)	(111,458)
Net proceeds from the sale of Class A Common Stock		0
Dividends paid on Class A and Class B Common Stock	0	0
Increase (decrease) in intercompany payables	(5,016)	(40,939)
Other, net	(3,539)	(16,107)
Net cash flows (used in) from financing activities	(10,592)	(165,084)
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	(14,224)	8,942
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of period	26,727	17,012
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of period	12,503	25,954
Eliminations
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
NET CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES	5,185	(466)
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Acquisition of property and equipment	0	181
Acquisition of businesses, net of cash acquired		0
Proceeds from the sale of assets	0	0
Investments in equity and cost method investees	0	0
Distributions from equity and cost method investees	0	0
Other, net	0	0
Net cash flows (used in) from investing activities	0	181
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable and commercial bank financing	0	0
Repayments of notes payable, commercial bank financing and capital leases	93	0
Net proceeds from the sale of Class A Common Stock		0
Dividends paid on Class A and Class B Common Stock	0	0
Increase (decrease) in intercompany payables	(5,278)	210
Other, net	0	75
Net cash flows (used in) from financing activities	(5,185)	285
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH	0	0
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of period	0	0
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of period	$ 0	$ 0

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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