Finance Receivables (Investment Of Wholesale Finance Receivables By Internal And External Credit Quality Indicator) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	$ 7,008,801	$ 7,015,331	$ 6,560,245	$ 6,110,256	$ 5,889,519
Retail
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	5,982,211	5,991,471	5,607,924	5,265,044	5,073,115
Retail | Prime
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	4,768,420	4,777,448
Retail | Sub-prime
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	1,213,791	1,214,023
Wholesale
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	1,026,590	1,023,860	$ 952,321	$ 845,212	$ 816,404
Wholesale | Doubtful
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	1,333	5,169
Wholesale | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	1,773	21,774
Wholesale | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	30,152	6,271
Wholesale | Medium Risk
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	14,620	11,494
Wholesale | Low Risk
Financing Receivable, Recorded Investment [Line Items]
Financing receivable, gross	$ 978,712	$ 979,152