Business Acquisitions and Investments - Schedule of Pro Forma Financial Information (Detail) - MAS Automotive Distribution Inc [Member] $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($) $ / shares
Business Acquisition [Line Items]
Net sales	$ 702,811
Net income	$ 85,307
Diluted earnings per share \| $ / shares	$ 2.49

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.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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