Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 11,721
Included in earnings	(256)
Included in other comprehensive income	1,038	(438)	1,132
Included in other comprehensive income	(8)	69	85
Interest income on Residuals	1,834us-gaap_OtherIncome	2,290us-gaap_OtherIncome	2,673us-gaap_OtherIncome
Cash received from Residuals	(2,711)
Purchases, sales, issuances and settlements, net	0
Transfers in and/or out of Level 3	0
Balance at end of period	11,626	11,721
Changes in gains (losses) included in earnings attributable to a change in unrealized gains (losses) relating to assets still held at the end of period	$ 163

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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Amount of purchases, (sales), issuances and (settlements) of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

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The cash inflow from the collection of a retained interest in a receivable securitized via a structured process whereby interests in loans and other receivables are packaged, underwritten, and sold in the form of asset-backed securities, categorized as available-for-sale.

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