Sales of Accounts Receivable and Receivable Discount Program - Additional Information (Detail) - Trade Accounts Receivable [Member] - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from sale of accounts receivable	$ 4,733	$ 11,345
Selling, General and Administrative Expenses [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Pre-tax losses on accounts receivable	$ 5	$ 34

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale, the carrying amounts, net of allocated reserves, of accounts receivable transferred to a third party in a transaction that qualifies for sales treatment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109247956&loc=d3e107425-111719

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow associated with the proceeds from sale and collection of receivables during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

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- Details

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- Details

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