Loan Loss Allowance and Credit Quality - Summary of Defaults in Loan Modifications Accounted as TDRs (Details) (Retail Installment Contracts, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014 Contract	Mar. 31, 2013 Contract
Retail Installment Contracts
Financing Receivable Modifications [Line Items]
Troubled debt restructurings that subsequently defaulted	$ 11,389	$ 10,072
Number of contracts	1,348	822

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953682-111524

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Balance Type:	debit
Period Type:	duration