Significant Accounting Policies - Tuition Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Tuition receivable	$ 83,960	$ 82,454
Allowance for credit losses	(42,956)	(30,931)
Tuition receivable, net	$ 41,004	$ 51,523

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 current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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