Vehicle Service Agreement Liability Reconciliation of the changes in the vehicle service agreement (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Movement in Standard Product Warranty Accrual [Roll Forward]
Recognition of service fees on vehicle service agreements		$ (11,300)
Vehicle service agreement fees
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at January 1, net	$ 43,734	40,794
Vehicle service agreement liability acquired during the year related to the purchase of Geminus	10,792	0
Gross service fees for vehicle service agreements sold	22,941	17,247
Recognition of service fees on vehicle service agreements	(20,489)	(14,421)
Liability for claims authorized on vehicle service agreements	6,838	4,206
Payments of claims authorized on vehicle service agreements	(4,305)	(4,378)
Re-estimation of deferred service fees	(351)	(252)
Balance at September 30, net	$ 59,160	$ 43,196

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

No definition available.

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- Definition

Amount as of the balance sheet date of the aggregate extended product warranty liability. Does not include the ending balance for the standard product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1),(c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Liability for an extended product warranty acquired in a business acquisition. Does not include any liability for a standard warranty acquired in a business acquisition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Amount of decrease in the extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the extended product warranty. Excludes standard product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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Amount of increase in the extended product warranty accrual from warranties issued. Excludes standard product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount, after effects of reinsurance, of payments to settle insured claims and pay costs incurred in the claims settlement process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437

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-Publisher FASB
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-Section 45
-Paragraph 25
-Subparagraph (g)
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Amount of increase (decrease) in the standard product warranty accrual from changes in estimates attributable to preexisting product warranties. Excludes extended product warranties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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