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Revenue Recognition - Additional Information (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
Revenue Recognition [Line Items]          
Length of academic year     210 days    
Revenue recognized estimated reserve based on historical evidence $ 2.3   $ 2.3   $ 2.3
ASC Topic 606 [Member]          
Revenue Recognition [Line Items]          
Revenue recognized for payments received from withdrawn students $ 0.5 $ 0.3 $ 0.9 $ 0.6  
Minimum [Member]          
Revenue Recognition [Line Items]          
Length of academic terms     56 days    
Maximum [Member]          
Revenue Recognition [Line Items]          
Length of academic terms     84 days