Fair Value of Financial Instruments (Servicing Rights) (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Minimum
Servicing Assets at Fair Value [Line Items]
Discount rate	30.00%	30.00%
Cost of service	0.09%	0.09%
Renewal rate	41.14%	46.20%
Default rate	10.21%	10.32%
Maximum
Servicing Assets at Fair Value [Line Items]
Discount rate	30.00%	30.00%
Cost of service	0.13%	0.14%
Renewal rate	55.79%	56.54%
Default rate	10.69%	10.75%
Weighted Average
Servicing Assets at Fair Value [Line Items]
Discount rate	30.00%	30.00%
Cost of service	0.11%	0.11%
Renewal rate	50.86%	50.14%
Default rate	10.37%	10.48%

Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Cost of Service

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- Definition

Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Default Rate

+ References

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- Definition

Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Renewal Rate

+ References

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122596-111746

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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