Restructuring Charges - Additional Information (Detail) $ in Thousands	3 Months Ended	9 Months Ended	45 Months Ended
Sep. 30, 2018 USD ($) Cmp	Sep. 30, 2018 USD ($) Cmp	Sep. 30, 2018 USD ($) Cmp	Dec. 31, 2017 USD ($)
Restructuring And Related Activities [Abstract]
Number of remaining campuses expected to cease operations \| Cmp	2	2	2
Severance and related costs	$ 1,898	$ 1,898
Accrual for severance and related charges	2,300	2,300	$ 2,300	$ 2,100
Accrued retention bonuses	$ 300	$ 300	300	$ 500
Charges related to remaining obligations for continuing operations			$ 75,600

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration