Revenue - Schedule of U.K. Revenue Attributed to Each Category (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 789,362	$ 765,738	$ 1,549,979	$ 1,507,979
U.K. Facilities [Member]
Disaggregation of Revenue [Line Items]
Revenue	279,549	284,268	552,206	564,104
U.K. Facilities [Member] \| Health Care Facilities [Member]
Disaggregation of Revenue [Line Items]
Revenue	155,553	158,894	307,261	313,509
U.K. Facilities [Member] \| Education and Children's Services [Member]
Disaggregation of Revenue [Line Items]
Revenue	46,142	48,065	92,264	96,150
U.K. Facilities [Member] \| Adult Care Facilities [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 77,854	$ 77,309	$ 152,681	$ 154,445

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration