CONDENSED CONSOLIDATING FINANCIAL STATEMENTS: (Details) (USD $)	Mar. 31, 2013		Dec. 31, 2012		Mar. 31, 2012	Dec. 31, 2011	Apr. 02, 2013 5.375% Senior Unsecured Notes, due 2021	Mar. 31, 2013 6.125% Senior Unsecured Notes, due 2022	Mar. 31, 2013 8.375% Senior Notes due 2018	Mar. 31, 2013 9.25% Senior Secured Second Lien Notes due 2017	Mar. 31, 2013 4.875% Notes	Mar. 31, 2013 3.0% Notes	Dec. 31, 2012 6.0% Notes	Mar. 31, 2013 Sinclair Broadcast Group, Inc.	Dec. 31, 2012 Sinclair Broadcast Group, Inc.	Mar. 31, 2013 Sinclair Broadcast Group, Inc. 4.875% Notes	Mar. 31, 2013 Sinclair Broadcast Group, Inc. 3.0% Notes	Dec. 31, 2011 Sinclair Broadcast Group, Inc. 6.0% Notes	Mar. 31, 2013 Sinclair Television Group, Inc.	Dec. 31, 2012 Sinclair Television Group, Inc.	Mar. 31, 2012 Sinclair Television Group, Inc.	Dec. 31, 2011 Sinclair Television Group, Inc.	Mar. 31, 2013 Sinclair Television Group, Inc. 5.375% Senior Unsecured Notes, due 2021	Mar. 31, 2013 Sinclair Television Group, Inc. 6.125% Senior Unsecured Notes, due 2022	Mar. 31, 2013 Sinclair Television Group, Inc. 8.375% Senior Notes due 2018	Mar. 31, 2013 Sinclair Television Group, Inc. 9.25% Senior Secured Second Lien Notes due 2017	Mar. 31, 2013 Guarantor Subsidiaries and KDSM, LLC	Dec. 31, 2012 Guarantor Subsidiaries and KDSM, LLC	Mar. 31, 2012 Guarantor Subsidiaries and KDSM, LLC	Dec. 31, 2011 Guarantor Subsidiaries and KDSM, LLC	Mar. 31, 2013 Non-Guarantor Subsidiaries	Dec. 31, 2012 Non-Guarantor Subsidiaries	Mar. 31, 2012 Non-Guarantor Subsidiaries	Dec. 31, 2011 Non-Guarantor Subsidiaries	Mar. 31, 2013 Eliminations	Dec. 31, 2012 Eliminations
CONDENSED CONSOLIDATING BALANCE SHEET
Interest rate (as a percent)							5.375%	6.125%	8.375%	9.25%	4.875%	3.00%	6.00%			4.875%	3.00%	6.00%					5.375%	6.125%	8.375%	9.25%
Debt related to STG and its subsidiaries	$ 2,270,900,000													$ 2,128,700,000					$ 2,182,400,000
Cash	25,825,000		22,865,000		26,802,000	12,967,000													6,499,000	7,230,000	17,311,000	188,000					656,000	199,000	980,000	313,000	18,670,000	15,436,000	8,511,000	12,466,000
Accounts and other receivables	198,108,000		183,896,000											87,000	152,000				830,000	907,000							192,134,000	175,837,000			6,596,000	7,622,000			(1,539,000)	(622,000)
Other current assets	53,285,000		67,330,000											587,000	2,821,000				3,408,000	2,342,000							42,494,000	56,522,000			8,756,000	9,028,000			(1,960,000)	(3,383,000)
Assets held for sale	15,714,000		30,357,000																								15,714,000	30,357,000
Total current assets	292,932,000		304,448,000											674,000	2,973,000				10,737,000	10,479,000							250,998,000	262,915,000			34,022,000	32,086,000			(3,499,000)	(4,005,000)
Property and equipment, net	431,542,000		439,713,000											5,972,000	6,315,000				9,481,000	8,938,000							318,131,000	321,873,000			108,759,000	113,454,000			(10,801,000)	(10,867,000)
Investment in consolidated subsidiaries																			1,655,442,000	1,636,504,000							1,927,000	1,956,000							(1,657,369,000)	(1,638,460,000)
Restricted cash - long-term	25,170,000		225,000																24,947,000	2,000							223,000	223,000
Other long-term assets	206,886,000		202,751,000											83,808,000	84,055,000				392,485,000	375,687,000							54,184,000	60,114,000			132,134,000	112,757,000			(455,725,000)	(429,862,000)
Total other long-term assets	232,056,000		202,976,000											83,808,000	84,055,000				2,072,874,000	2,012,193,000							56,334,000	62,293,000			132,134,000	112,757,000			(2,113,094,000)	(2,068,322,000)
Acquired intangible assets	1,777,998,000		1,782,560,000																								1,701,289,000	1,706,646,000			162,188,000	153,961,000			(85,479,000)	(78,047,000)
Total assets	2,734,528,000	[1]	2,729,697,000	[1]										90,454,000	93,343,000				2,093,092,000	2,031,610,000							2,326,752,000	2,353,727,000			437,103,000	412,258,000			(2,212,873,000)	(2,161,241,000)
Accounts payable and accrued liabilities	176,252,000		153,817,000											511,000	326,000				90,902,000	61,165,000							74,960,000	83,049,000			10,501,000	9,379,000			(622,000)	(102,000)
Current portion of long-term debt	46,366,000		47,622,000											500,000	483,000				32,662,000	31,113,000							853,000	800,000			12,351,000	15,226,000
Current portion of affiliate long-term debt	2,090,000		1,704,000											1,176,000	1,102,000												914,000	602,000			742,000	433,000			(742,000)	(433,000)
Other current liabilities	84,508,000		102,060,000											2,638,000													75,352,000	96,288,000			8,194,000	8,871,000			(1,676,000)	(3,099,000)
Liabilities held for sale	1,948,000		2,397,000																								1,948,000	2,397,000
Total current liabilities	311,164,000		307,600,000											4,825,000	1,911,000				123,564,000	92,278,000							154,027,000	183,136,000			31,788,000	33,909,000			(3,040,000)	(3,634,000)
Long-term debt	2,201,629,000		2,210,866,000											12,415,000	12,502,000				2,071,357,000	2,088,586,000							36,476,000	36,705,000			81,381,000	73,073,000
Affiliate long-term debt	20,777,000		13,187,000											5,953,000	6,303,000												14,824,000	6,884,000			272,636,000	267,521,000			(272,636,000)	(267,521,000)
Dividends in excess of investment in consolidated subsidiaries														116,435,000	178,869,000																				(116,435,000)	(178,869,000)
Other liabilities	298,245,000		298,097,000											55,554,000	10,708,000				5,864,000	2,509,000							467,025,000	491,845,000			113,047,000	103,007,000			(343,245,000)	(309,972,000)
Total liabilities	2,831,815,000	[1]	2,829,750,000	[1]										195,182,000	210,293,000				2,200,785,000	2,183,373,000							672,352,000	718,570,000			498,852,000	477,510,000			(735,356,000)	(759,996,000)
Common stock	817,000		812,000											817,000	812,000												10,000	10,000							(10,000)	(10,000)
Additional paid-in capital	608,235,000		600,928,000											608,235,000	600,928,000				(192,086,000)	(175,973,000)							1,012,966,000	1,084,302,000			66,747,000	64,096,000			(887,627,000)	(972,425,000)
Accumulated (deficit) earnings	(708,748,000)		(713,697,000)											(708,748,000)	(713,697,000)				87,813,000	27,597,000							644,410,000	553,777,000			(139,840,000)	(147,299,000)			(592,383,000)	(434,075,000)
Accumulated other comprehensive (loss) income	(5,032,000)		(4,993,000)											(5,032,000)	(4,993,000)				(3,420,000)	(3,387,000)							(2,986,000)	(2,932,000)			3,903,000	1,054,000			2,503,000	5,265,000
Total Sinclair Broadcast Group shareholders' deficit	(104,728,000)		(116,950,000)											(104,728,000)	(116,950,000)				(107,693,000)	(151,763,000)							1,654,400,000	1,635,157,000			(69,190,000)	(82,149,000)			(1,477,517,000)	(1,401,245,000)
Noncontrolling interests in consolidated subsidiaries	7,441,000		16,897,000																												7,441,000	16,897,000
Total liabilities and equity (deficit)	$ 2,734,528,000		$ 2,729,697,000											$ 90,454,000	$ 93,343,000				$ 2,093,092,000	$ 2,031,610,000							$ 2,326,752,000	$ 2,353,727,000			$ 437,103,000	$ 412,258,000			$ (2,212,873,000)	$ (2,161,241,000)

[1] Our consolidated total assets as of March 31, 2013 and December 31, 2012 include total assets of variable interest entities (VIEs) of $113.0 million and $107.9 million, respectively, which can only be used to settle the obligations of the VIEs. Our consolidated total liabilities as of March 31, 2013 and December 31, 2012 include total liabilities of the VIEs of $13.0 million and $7.9 million, respectively, for which the creditors of the VIEs have no recourse to us.