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Nature of Business - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2018 Degrees Colleges
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of area of the company's campus in Phoenix, Arizona	275 acre campus
Number of colleges in Phoenix, Arizona | Colleges	9
Number of degree programs and certificates | Degrees	225

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Number of colleges.

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Number of degree programs offered.

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Real estate property description.

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