Goodwill and Other Intangible Assets (Changes in Carrying Amount of Goodwill) (Details 1) $ in Thousands	3 Months Ended
	Mar. 31, 2018 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,665,861
Accumulated impairment losses, beginning balance	(366,151)
Goodwill, net, beginning balance	1,299,710
Acquisitions	963
Dispositions	(11,191)
Foreign currency exchange rate changes	12,002
Goodwill, ending balance	1,647,936
Accumulated impairment losses, ending balance	(346,452)
Goodwill, net, ending balance	1,301,484
Education [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	1,171,812
Accumulated impairment losses, beginning balance	(350,850)
Goodwill, net, beginning balance	820,962
Reallocation	0
Acquisitions	963
Dispositions	(11,191)
Foreign currency exchange rate changes	12,002
Goodwill, ending balance	1,153,887
Accumulated impairment losses, ending balance	(331,151)
Goodwill, net, ending balance	822,736
Education [Member] | Kaplan International [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	615,861
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	615,861
Reallocation	0
Acquisitions	26
Dispositions	0
Foreign currency exchange rate changes	12,047
Goodwill, ending balance	627,934
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	627,934
Education [Member] | Higher Education [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	389,853
Accumulated impairment losses, beginning balance	(248,591)
Goodwill, net, beginning balance	141,262
Reallocation	(66,791)
Acquisitions	0
Dispositions	(11,191)
Foreign currency exchange rate changes	(40)
Goodwill, ending balance	174,564
Accumulated impairment losses, ending balance	(111,324)
Goodwill, net, ending balance	63,240
Education [Member] | Test Preparation [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	166,098
Accumulated impairment losses, beginning balance	(102,259)
Goodwill, net, beginning balance	63,839
Reallocation	0
Acquisitions	937
Dispositions	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	167,035
Accumulated impairment losses, ending balance	(102,259)
Goodwill, net, ending balance	64,776
Education [Member] | Professional (U.S.) [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	0
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	0
Reallocation	66,791
Acquisitions	0
Dispositions	0
Foreign currency exchange rate changes	(5)
Goodwill, ending balance	184,354
Accumulated impairment losses, ending balance	(117,568)
Goodwill, net, ending balance	66,786
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
Dispositions	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	190,815
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	190,815
Healthcare [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	69,409
Accumulated impairment losses, beginning balance	0
Goodwill, net, beginning balance	69,409
Acquisitions	0
Dispositions	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	69,409
Accumulated impairment losses, ending balance	0
Goodwill, net, ending balance	69,409
Other Businesses [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	233,825
Accumulated impairment losses, beginning balance	(15,301)
Goodwill, net, beginning balance	218,524
Acquisitions	0
Dispositions	0
Foreign currency exchange rate changes	0
Goodwill, ending balance	233,825
Accumulated impairment losses, ending balance	(15,301)
Goodwill, net, ending balance	$ 218,524