Goodwill and Other Intangible Assets (Other Intangible Assets) (Details 2) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	$ 579,378	$ 581,877
Accumulated Amortization	362,766	334,757
Net Carrying Amount	216,612	247,120
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	137,545	142,180
Trade Names and Trademarks [Member]
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	82,316	86,972
Franchise Agreements [Member]
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	44,058	44,058
FCC licenses [Member]
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	11,000	11,000
Licensure and Accreditation [Member]
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	150	150
Other [Member]
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets	21	0
Student and Customer Relationships [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	297,886	300,027
Accumulated Amortization	218,349	206,714
Net Carrying Amount	$ 79,537	$ 93,313
Student and Customer Relationships [Member] | Minimum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	2 years	2 years
Student and Customer Relationships [Member] | Maximum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	10 years	10 years
Trade Names and Trademarks [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	$ 158,006	$ 158,365
Accumulated Amortization	75,092	68,113
Net Carrying Amount	$ 82,914	$ 90,252
Trade Names and Trademarks [Member] | Minimum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	2 years	2 years
Trade Names and Trademarks [Member] | Maximum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	15 years	15 years
Databases and Technology [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	$ 36,186	$ 36,585
Accumulated Amortization	29,309	26,464
Net Carrying Amount	$ 6,877	$ 10,121
Databases and Technology [Member] | Minimum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	3 years	3 years
Databases and Technology [Member] | Maximum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	6 years	6 years
Network Affiliation Agreements [Member]
Amortized Intangible Assets [Line Items]
Useful Life	10 years	10 years
Gross Carrying Amount	$ 17,400	$ 17,400
Accumulated Amortization	9,497	8,628
Net Carrying Amount	7,903	8,772
Non-compete Agreements [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	1,000	1,000
Accumulated Amortization	993	991
Net Carrying Amount	$ 7	$ 9
Non-compete Agreements [Member] | Minimum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	2 years	2 years
Non-compete Agreements [Member] | Maximum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	5 years	5 years
Other [Member]
Amortized Intangible Assets [Line Items]
Gross Carrying Amount	$ 68,900	$ 68,500
Accumulated Amortization	29,526	23,847
Net Carrying Amount	$ 39,374	$ 44,653
Other [Member] | Minimum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	1 year	1 year
Other [Member] | Maximum [Member]
Amortized Intangible Assets [Line Items]
Useful Life	8 years	8 years