Fair Value Measurements (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) securitization	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Fair Value Disclosures [Abstract]
Transferor's Interests in Transferred Financial Assets, Fair Value	$ 36	$ 11,115
Number of residual interests held from securitizations \| securitization	2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Included in earnings	$ (6,983)
Included in other comprehensive income	(4,454)	(339)	$ 1,038
Interest income on Residuals	1,677	$ 1,778	$ 1,834
Cash received from Residuals	(1,319)
Purchases, sales, issuances and settlements, net	0
Transfers in and/or out of Level 3	0
Balance at end of year	36
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	$ 4,272

Number of Residual Interests Held from Securitizations

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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- Definition

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.

+ References

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The carrying amount (fair value) as of the balance sheet date of the transferor's interests in transferred financial assets (typically securitized receivables, generally not involved in the collection of principal) following transfer of significant portions of such financial instruments to other parties. Such interests could be ancillary cash flows and interest-only strips.

+ References

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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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Amount of revenue and income classified as other.

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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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