Detail of Certain Balance Sheet Accounts (Accounts and Notes Receivable) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accounts and notes receivable
Total accounts and notes receivable	$ 190,615	$ 176,260
Less allowance for doubtful accounts	2,943	2,896
Accounts and notes receivable, net	187,672	173,364
Amounts due from manufacturers [Member]
Accounts and notes receivable
Total accounts and notes receivable	111,768	95,754
Parts and service receivables [Member]
Accounts and notes receivable
Total accounts and notes receivable	38,523	35,318
Finance and insurance receivables, net [Member]
Accounts and notes receivable
Total accounts and notes receivable	23,681	24,866
Other [Member]
Accounts and notes receivable
Total accounts and notes receivable	$ 16,643	$ 20,322

The aggregate of amounts due from customers or clients, within one year of the balance sheet date (or one operating cycle, if longer), for goods or services that have been delivered or sold in the normal course of business and an amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date within one year of the balance sheet, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection and net of any write-downs taken for collection uncertainty on the part of the holder, respectively.

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- References

No definition available.

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(5))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.4)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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