Number of pending program reviews.

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Number of pending claims pertaining to a loss contingency.

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Amount of noncurrent assets classified as other.

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Contingencies (Details) $ in Thousands, £ in Millions	Sep. 30, 2018 USD ($) claim program_review	Sep. 30, 2018 GBP (£) claim program_review	Dec. 31, 2017 USD ($)
Loss Contingencies [Line Items]
Number of existing legal claims or proceedings that are likely to have a material effect on the Company's business \| claim	0	0
Deferred Charges and Other Assets	$ 117,149		$ 102,046
Maximum [Member]
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	45,000
Education [Member] \| Sale of KHE Campuses business [Member]
Loss Contingencies [Line Items]
Secondarily Liable Leases	$ 16,300
Education [Member] \| Sale of KHE Campuses business [Member] \| Higher Education [Member]
Loss Contingencies [Line Items]
Number of pending program reviews \| program_review	2	2
Her Majesty's Revenue and Customs (HMRC) [Member] \| UK Pathways [Member] \| Kaplan International [Member]
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss \| £		£ 15.4
Deferred Charges and Other Assets \| £		£ 15.4