Accounting policies.

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Amount of funds authorized by students to be retained which are in excess of tuition billings.

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Loans receivable repayment period.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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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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Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 USD ($) Segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Accounting Policies [Line Items]
Number of reporting segments \| Segment	2
Securitization of letters of credit	$ 0	$ 300,000
Advertising costs	$ 130,900,000	$ 126,400,000	$ 136,100,000
CCKF [Member]
Accounting Policies [Line Items]
Percentage of investment in equity affiliate	30.70%
Non controlling interest	$ 2,700,000
Title IV Programs [Member]
Accounting Policies [Line Items]
Student fund portion in cash, and cash equivalents	$ 9,600,000
Maximum [Member]
Accounting Policies [Line Items]
Maturity period of cash equivalents including short-term investments	three months
Lease term range, years	10 years
Number of renewal options for extended terms	4 years
Minimum [Member]
Accounting Policies [Line Items]
Number of days past due to write off student receivables	90 days
Lease term range, years	5 years
Number of renewal options for extended terms	1 year
Student Loans [Member] \| Maximum [Member] \| Current Assets [Member]
Accounting Policies [Line Items]
Student receivables period	1 year
Student Loans [Member] \| Minimum [Member] \| Non Current Assets [Member]
Accounting Policies [Line Items]
Student receivables period	1 year
Cash Receipts [Member] \| Credit Concentration Risk [Member]
Accounting Policies [Line Items]
Percentage of cash receipts from Title IV Program funding	79.00%	79.00%	78.00%