Victory Motorcycles Wind Down (Wind Down Charges) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017
Victory Motorcycles \| Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations, Abandonment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charges related to the wind down plan	$ 1,242	$ 56,465	$ 10,683

Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109222650&loc=SL51721673-107760

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationOperatingExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration