Contingent consideration gain related to the sale of a business.

No definition available.

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- Definition

The number of businesses disposed of by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

[Line Items] for Schedule of Non-Operating Income (Expense) [Table]

+ References

No definition available.

+ Details

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- Definition

Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117539-209714

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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Other Non-Operating Income (Narrative) (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) business	Sep. 30, 2017 USD ($)
Schedule of Non-Operating Income (Expense) [Line Items]
Gain on cost method investments	$ 8,487		$ 0	$ 8,487	$ 0
Gain (loss) on sales of businesses	916		$ 0	8,157	$ (342)
Education [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Gain (loss) on sales of businesses				$ 8,200
Number of businesses disposed \| business				3
Higher Education [Member] \| Education [Member] \| Kaplan University Transaction [Member]
Schedule of Non-Operating Income (Expense) [Line Items]
Gain (loss) on sales of businesses		$ 4,300		$ 4,300
Gain Related to Contingent Consideration	$ 500			$ 1,900