Segment Reporting - Summary Financial Information by Reporting Segment (Parenthetical) (Detail) $ in Millions	Jun. 30, 2019 USD ($)
CTU [Member]
Segment Reporting Information [Line Items]
Settlement reserve	$ 18.6
AIU [Member]
Segment Reporting Information [Line Items]
Settlement reserve	$ 11.4

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.

No definition available.

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