Property and Equipment - Additional information (Detail) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($) Bed	Dec. 31, 2018 USD ($)
Other Assets [Member]
Property, Plant and Equipment [Line Items]
Assets held for sale \| $	$ 10.9	$ 17.0
Residential Treatment Centers [Member] \| Albuquerque, New Mexico [Member]
Property, Plant and Equipment [Line Items]
Number of beds in facilities closed \| Bed	168

Amount of assets held-for-sale that are not part of a disposal group.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=77912953&loc=d3e400-110220

Name:	us-gaap_AssetsHeldForSaleNotPartOfDisposalGroup
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant