CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income		$ 345,998	$ 594,104	[1]	$ 250,762	[1]
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation of property and equipment		105,240	97,103	[1]	98,529	[1]
Amortization of definite-lived intangible and other assets		174,848	178,822	[1]	183,795	[1]
Amortization of program contract costs and net realizable value adjustments		100,899	115,523	[1]	127,880	[1]
Loss on extinguishment of debt		0	1,404	[1]	23,699	[1]
Stock-based compensation		26,516	15,886	[1]	16,939	[1]
Deferred tax (benefit) provision		(102,621)	(159,462)	[1]	6,118	[1]
Gain on asset dispositions, net of impairment		(19,325)	(278,608)	[1]	(6,029)	[1]
Loss (income) from equity method investments		60,831	14,307	[1]	(906)	[1]
Changes in assets and liabilities, net of effects of acquisitions and dispositions:
Increase in accounts receivable		(36,680)	(41,908)	[1]	(71,718)	[1]
Net change in net income taxes payable/receivable		48,703	(43,374)	[1]	18,814	[1]
Increase in prepaid expenses and other current assets		(9,905)	(9,409)	[1]	(969)	[1]
Increase in accounts payable and accrued liabilities		23,666	34,857	[1]	60,086	[1]
Payments on program contracts payable		(107,983)	(111,470)	[1]	(111,506)	[1]
Other, net		37,231	23,638	[1]	16,096	[1]
Net cash flows from operating activities		647,418	431,413	[1]	611,590	[1]
CASH FLOWS (USED IN) FROM INVESTING ACTIVITIES:
Acquisition of property and equipment		(105,061)	(83,812)	[1]	(94,465)	[1]
Acquisition of businesses, net of cash acquired		0	(271,273)	[1]	(425,657)	[1]
Spectrum auction proceeds		0	310,802	[1]	0	[1]
Proceeds from the sale of assets		1,616	195,209	[1]	17,202	[1]
Purchase of alarm monitoring contracts		0	(5,682)	[1]	(40,206)	[1]
Investments in equity investees		(35,805)	(55,129)	[1]	(51,247)	[1]
Distributions from equity method investees		22,834	12,178	[1]	6,786	[1]
Loans to affiliates		0	19,500	[1]	(19,500)	[1]
Other, net		(1,795)	(7,209)	[1]	(2,441)	[1]
Net cash flows (used in) from investing activities		(118,211)	114,584	[1]	(609,528)	[1]
CASH FLOWS (USED IN) FROM FINANCING ACTIVITIES:
Proceeds from notes payable, commercial bank financing and capital leases		4,317	166,797	[1]	1,024,912	[1]
Repayments of notes payable, commercial bank financing and capital leases		(166,785)	(340,108)	[1]	(674,439)	[1]
Proceeds from the sale of Class A Common Stock		0	487,883	[1]	0	[1]
Repurchase of outstanding Class A Common Stock		(220,889)	(30,287)	[1]	(136,283)	[1]
Dividends paid on Class A and Class B Common Stock		(74,566)	(71,364)	[1]	(65,909)	[1]
Payments for deferred financing costs		(922)	(731)	[1]	(35,505)	[1]
Distributions to noncontrolling interests		(8,901)	(22,416)	[1]	(10,464)	[1]
Other, net		2,929	(15)	[1]	2,113	[1]
Net cash flows (used in) from financing activities		(464,817)	189,759	[1]	104,425	[1]
NET INCREASE IN CASH, CASH EQUIVALENTS, AND RESTRICTED CASH		64,390	735,756	[1]	106,487	[1]
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, beginning of year	[1]	995,940	260,184		153,697
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH, end of year		$ 1,060,330	$ 995,940	[1]	$ 260,184	[1]

[1] See Recent Accounting Pronouncements within Note 1. Nature of Operations and Summary of Significant Accounting Policies for a discussion of the adoption of new accounting principles related to the classification of certain cash receipts and cash payments.