NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES: (Details 4) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012 item	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012 item	Dec. 31, 2011	Dec. 31, 2010
Variable Interest Entities
Number of television stations owned	87								87
Net revenue	$ 329,517,000	$ 258,713,000	$ 251,074,000	$ 222,375,000	$ 212,776,000	$ 181,042,000	$ 188,861,000	$ 182,609,000	$ 1,061,679,000	$ 765,288,000	$ 767,644,000
Net broadcast revenues									920,593,000	648,002,000	655,836,000
Station production expenses									255,556,000	178,612,000	154,133,000
Income from equity and cost method investments									9,670,000	3,269,000	(4,861,000)
VIEs which are not primary beneficiary
Variable Interest Entities
Carrying amount	30,983,000				34,285,000				30,983,000	34,285,000
Maximum exposure	30,983,000				34,285,000				30,983,000	34,285,000
Income from equity and cost method investments									6,400,000	2,800,000	2,100,000
Unfunded commitments related to private equity investment funds	8,900,000				10,900,000				8,900,000	10,900,000
Freedom
Variable Interest Entities
Net broadcast revenues				10,000,000					10,000,000
Station production expenses									7,800,000
Four Points and Freedom
Variable Interest Entities
Net revenue										10,800,000
Station production expenses										7,700,000
Investments in real estate ventures
Variable Interest Entities
Carrying amount	3,648,000				8,009,000				3,648,000	8,009,000
Maximum exposure	3,648,000				8,009,000				3,648,000	8,009,000
Investments in investment companies
Variable Interest Entities
Carrying amount	27,335,000				26,276,000				27,335,000	26,276,000
Maximum exposure	$ 27,335,000				$ 26,276,000				$ 27,335,000	$ 26,276,000