Employee Benefits - Schedule of Insurance Receivable for Claims (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Workers' Compensation [Member]
Malpractice Insurance [Line Items]
Included in other non-current assets	$ 1,827	$ 1,826

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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