Segment Information (Summary of Continuing Operations by Reportable Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Revenues, net	$ 810,766	$ 654,015	$ 2,273,899	$ 2,034,681
Operating income (loss)	188,326	139,477	426,290	361,249
Share-based compensation expense	9,455	12,394	39,163	43,141
Depreciation and amortization	23,411	27,547	71,261	80,182
Impairment and other charges	0	0	158,973	130,411
Restructuring and other related charges	754	4,406	9,534	13,879
Cloud computing amortization	596		1,502
Majority-owned equity investees AOI	2,149	1,667	6,584	4,361
Adjusted operating income (loss)	224,691	185,491	713,307	633,223
Operating segments | Domestic Operations
Segment Reporting Information [Line Items]
Revenues, net	682,746	546,865	1,895,730	1,721,690
Operating income (loss)	213,299	179,259	517,874	621,446
Share-based compensation expense	4,174	4,437	17,105	12,005
Depreciation and amortization	11,589	15,799	36,678	38,050
Impairment and other charges			143,000	0
Restructuring and other related charges	(135)	4,452	2,508	7,138
Cloud computing amortization	0		0
Majority-owned equity investees AOI	2,149	1,667	6,584	4,361
Adjusted operating income (loss)	231,076	205,614	723,749	683,000
Operating segments | International & Other
Segment Reporting Information [Line Items]
Revenues, net	129,940	111,398	389,384	326,908
Operating income (loss)	15,564	3,061	32,365	(118,140)
Share-based compensation expense	545	919	2,689	2,437
Depreciation and amortization	5,200	4,937	14,477	21,396
Impairment and other charges			15,973	130,411
Restructuring and other related charges	800	0	5,273	6,239
Cloud computing amortization	0		0
Majority-owned equity investees AOI	0	0	0	0
Adjusted operating income (loss)	22,109	8,917	70,777	42,343
Corporate / Inter-segment Eliminations
Segment Reporting Information [Line Items]
Revenues, net	(1,920)	(4,248)	(11,215)	(13,917)
Operating income (loss)	(40,537)	(42,843)	(123,949)	(142,057)
Share-based compensation expense	4,736	7,038	19,369	28,699
Depreciation and amortization	6,622	6,811	20,106	20,736
Impairment and other charges			0	0
Restructuring and other related charges	89	(46)	1,753	502
Cloud computing amortization	596		1,502
Majority-owned equity investees AOI	0	0	0	0
Adjusted operating income (loss)	(28,494)	(29,040)	(81,219)	(92,120)
Corporate / Inter-segment Eliminations | Domestic Operations
Segment Reporting Information [Line Items]
Revenues, net	(1,641)	(3,988)	(8,567)	(11,545)
Corporate / Inter-segment Eliminations | International & Other
Segment Reporting Information [Line Items]
Revenues, net	(279)	(260)	(2,648)	(2,372)
Advertising
Segment Reporting Information [Line Items]
Revenues, net	225,336	183,102	684,298	617,935
Advertising | Operating segments | Domestic Operations
Segment Reporting Information [Line Items]
Revenues, net	199,982	164,178	611,406	564,838
Advertising | Operating segments | International & Other
Segment Reporting Information [Line Items]
Revenues, net	25,354	18,924	72,892	53,097
Advertising | Corporate / Inter-segment Eliminations
Segment Reporting Information [Line Items]
Revenues, net	0	0	0	0
Distribution and other
Segment Reporting Information [Line Items]
Revenues, net	585,430	470,913	1,589,601	1,416,746
Distribution and other | Operating segments | Domestic Operations
Segment Reporting Information [Line Items]
Revenues, net	482,764	382,687	1,284,324	1,156,852
Distribution and other | Operating segments | International & Other
Segment Reporting Information [Line Items]
Revenues, net	104,586	92,474	316,492	273,811
Distribution and other | Corporate / Inter-segment Eliminations
Segment Reporting Information [Line Items]
Revenues, net	$ (1,920)	$ (4,248)	$ (11,215)	$ (13,917)