Goodwill and Other Intangible Assets (Changes in Carrying Amount of Goodwill) (Details 1) $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,838,080
Accumulated impairment losses, beginning balance	(353,330)
Goodwill, net, beginning balance	1,484,750
Acquisitions	167,334
Impairment	(26,686)
Foreign currency exchange rate changes	(13,055)
Goodwill, ending balance	1,992,359
Accumulated impairment losses, ending balance	(380,016)
Goodwill, net, ending balance	1,612,343
Education [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	1,183,379
Accumulated impairment losses, beginning balance	(331,151)
Goodwill, net, beginning balance	852,228
Acquisitions	0
Impairment	0
Foreign currency exchange rate changes	(13,055)
Goodwill, ending balance	1,170,324
Accumulated impairment losses, ending balance	(331,151)
Goodwill, net, ending balance	839,173
Education [Member] | Kaplan International [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	634,749
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	634,749
Foreign currency exchange rate changes	(13,065)
Goodwill, ending balance	621,684
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	621,684
Education [Member] | Higher Education [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	174,564
Accumulated impairment losses, beginning balance	(111,324)
Goodwill, net, beginning balance	63,240
Foreign currency exchange rate changes	0
Goodwill, ending balance	174,564
Accumulated impairment losses, ending balance	(111,324)
Goodwill, net, ending balance	63,240
Education [Member] | Supplemental Education [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	374,066
Accumulated impairment losses, beginning balance	(219,827)
Goodwill, net, beginning balance	154,239
Foreign currency exchange rate changes	10
Goodwill, ending balance	374,076
Accumulated impairment losses, ending balance	(219,827)
Goodwill, net, ending balance	154,249
Television Broadcasting [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	190,815
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	190,815
Acquisitions	0
Impairment	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	190,815
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	190,815
Manufacturing [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	234,993
Accumulated impairment losses, beginning balance	(7,616)
Goodwill, net, beginning balance	227,377
Acquisitions	0
Impairment	(26,686)
Foreign currency exchange rate changes	0
Goodwill, ending balance	234,993
Accumulated impairment losses, ending balance	(34,302)
Goodwill, net, ending balance	200,691
Healthcare [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	98,421
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	98,421
Acquisitions	0
Impairment	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	98,421
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	98,421
Automotive [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	39,121
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	39,121
Acquisitions	0
Impairment	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	39,121
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	39,121
Other Businesses [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	91,351
Accumulated impairment losses, beginning balance	(14,563)
Goodwill, net, beginning balance	76,788
Acquisitions	167,334
Impairment	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	258,685
Accumulated impairment losses, ending balance	(14,563)
Goodwill, net, ending balance	$ 244,122