Victory Motorcycles Wind Down (Wind Down Charges) (Details) - Victory Motorcycles - Disposal Group, Disposed of by Means Other than Sale, Not Discontinued Operations, Abandonment - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charges related to the wind down plan	$ 1,388	$ 45,782
Contract termination charges
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charges related to the wind down plan	764	14,307
Asset impairment charges
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charges related to the wind down plan	0	18,760
Inventory charges
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charges related to the wind down plan	0	7,451
Other costs
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Charges related to the wind down plan	$ 624	$ 5,264