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Contingencies - Additional Information (Detail) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Contingencies And Commitments [Line Items] |  |
Maximum exposure associated with general indemnifications | $ 0.5 | $ 0.5
General indemnifications minimum expiration period | 1 year |
General indemnifications maximum expiration period | 3 years |
Contingent liability reserve balance after reduction | $ 2.8 | $ 2.8
Dealership [Member] |  |
Contingencies And Commitments [Line Items] |  |
Joint venture ownership percentage | 50.00% | 50.00%
Other Accrued Liabilities [Member] |  |
Contingencies And Commitments [Line Items] |  |
Amount reserved for pending proceedings | $ 2.5 | $ 0.3
Other Long-Term Liabilities [Member] |  |
Contingencies And Commitments [Line Items] |  |
Amount reserved for pending proceedings | $ 0.2 | $ 0.2

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- Definition Undiscounted amount of the accrual for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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