Business Acquisitions and Investments - Schedule of Valuation of Intangible Assets Acquired and Related Amortization Periods (Detail) - MAS Automotive Distribution Inc [Member] $ in Thousands	Oct. 26, 2017 USD ($)
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 20,440
Customer Relationships [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 14,840
Customer Relationships [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Amortization Period (in years)	8 years
Customer Relationships [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Amortization Period (in years)	12 years
Tradenames [Member]
Business Acquisition [Line Items]
Valuation,Intangible assets	$ 5,600
Amortization Period (in years)	15 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=108330185&loc=d3e2207-128464

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