Finance Receivables (Wholesale And Retail Receivables Accruing Interest And Are Past Due) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Receivables past due and accruing interest	$ 40,076	$ 40,725	$ 32,869	$ 28,918	$ 24,801
United States
Financing Receivable, Recorded Investment, Past Due [Line Items]
Receivables past due and accruing interest	39,051	39,399	31,677	27,800	23,770
Canada
Financing Receivable, Recorded Investment, Past Due [Line Items]
Receivables past due and accruing interest	$ 1,025	$ 1,326	$ 1,192	$ 1,118	$ 1,031