Finance Receivables (Investment Of Wholesale Finance Receivables By Internal And External Credit Quality Indicator) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	$ 7,015,331	$ 6,560,245	$ 6,110,256	$ 5,889,519	$ 5,912,130
Consumer Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	5,991,471	5,607,924	5,265,044	5,073,115	5,087,490
Consumer Portfolio Segment [Member] | Prime [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	4,777,448	4,435,352
Consumer Portfolio Segment [Member] | Sub Prime [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,214,023	1,172,572
Commercial Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	1,023,860	952,321	$ 845,212	$ 816,404	$ 824,640
Commercial Portfolio Segment [Member] | Doubtful [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	5,169	954
Commercial Portfolio Segment [Member] | Substandard [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	21,774	7,025
Commercial Portfolio Segment [Member] | Special Mention [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	6,271	0
Commercial Portfolio Segment [Member] | Risk Level, Medium [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	11,494	11,557
Commercial Portfolio Segment [Member] | Risk Level, Low [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, Gross	$ 979,152	$ 932,785