Business Acquisitions and Investments - Summary of Preliminary Fair Value of Total Consideration (Detail) - MAS Automotive Distribution Inc [Member] - USD ($) $ in Thousands		3 Months Ended
Oct. 26, 2017	Mar. 31, 2018
Business Acquisition [Line Items]
Cash consideration (net of $3.3 million cash received)	$ 56,859
Contingent cash consideration	7,982	$ 8,100
Seller liability assumed	896
Working capital adjustment	1,539
Total consideration assigned to net assets acquired	$ 67,276

Business combination contingent cash consideration.

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Business combination, working capital adjustment.

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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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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6405-128476

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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