Finance Receivables (Finance Receivables) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	$ 7,008,801	$ 7,015,331	$ 6,560,245	$ 6,110,256	$ 5,889,519
Allowance for credit losses	(173,343)	(147,178)	(127,364)	(110,693)	(107,667)
Total finance receivables, net	6,835,458	6,868,153	6,432,881	5,999,563	5,781,852
United States
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	6,730,560
Canada
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	278,241
Wholesale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	1,026,590	1,023,860	952,321	845,212	816,404
Allowance for credit losses	(6,582)	(7,858)	(5,339)	(4,630)
Wholesale | United States
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	961,150	965,379	903,380	800,491	776,633
Wholesale | Canada
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	65,440	58,481	48,941	44,721	39,771
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	5,982,211	5,991,471	5,607,924	5,265,044	5,073,115
Allowance for credit losses	(166,761)	(139,320)	(122,025)	(106,063)
Retail | United States
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	5,769,410	5,803,071	5,398,006	5,051,245	4,850,450
Retail | Canada
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, gross	$ 212,801	$ 188,400	$ 209,918	$ 213,799	$ 222,665