Advance related to Kaplan University Transaction.

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Amount of long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets, goodwill, and other intangible assets located in foreign countries in total in which the entity holds assets.

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Number of television broadcast stations owned by the Company.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as noncurrent.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Represents the number of restaurants.

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Represents the number of stores.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Business Segments (Narrative) (Details) $ in Thousands		3 Months Ended								12 Months Ended
Business Segments (Narrative) (Details) $ in Thousands	Mar. 22, 2018 USD ($)	Dec. 31, 2019 USD ($) TelevisionStation Restaurants	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) TelevisionStation Restaurants Segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment										8
Operating Revenues		$ 763,478	$ 738,820	$ 737,602	$ 692,199	$ 689,087	$ 674,766	$ 672,677	$ 659,436	$ 2,932,099	$ 2,695,966	$ 2,591,846
Television Broadcasting [Member]
Segment Reporting Information [Line Items]
Number of television broadcast stations owned \| TelevisionStation		7								7
Other Businesses [Member]
Segment Reporting Information [Line Items]
Number of Stores		3								3
Number of Restaurants \| Restaurants		13								13
Education [Member]
Segment Reporting Information [Line Items]
Restructuring costs												9,065
Accrued restructuring costs		$ 1,300				4,600				$ 1,300	4,600
Non U.S. [Member]
Segment Reporting Information [Line Items]
Operating Revenues										691,000	657,000	637,000
Foreign assets		431,000				$ 124,000				431,000	124,000
UNITED KINGDOM \| Education [Member]
Segment Reporting Information [Line Items]
Operating Revenues										384,000	$ 345,000	320,000
Higher Education [Member] \| Education [Member]
Segment Reporting Information [Line Items]
Restructuring costs												1,400
Test Preparation [Member] \| Education [Member]
Segment Reporting Information [Line Items]
Restructuring costs												4,300
Kaplan International [Member] \| Education [Member]
Segment Reporting Information [Line Items]
Restructuring costs												$ 2,900
Kaplan University Transaction [Member] \| Higher Education [Member] \| Education [Member] \| Purdue University Global [Member]
Segment Reporting Information [Line Items]
Accounts Receivable, after Allowance for Credit Loss		68,400								68,400
Accounts Receivable, after Allowance for Credit Loss, Noncurrent		$ 18,600								$ 18,600
Advance Related To Kaplan University Transaction	$ 20,000