MORTGAGE SERVICING RIGHTS - Summary of key assumptions (Details)	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Commercial FHA Mortgage Loans
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Servicing Fee	0.13%	0.13%
Interest Rate	3.70%	3.72%
Remaining Years to Maturity	30 years 3 months 18 days	30 years 2 months 12 days
Prepayment Rate	8.27%	8.31%
Servicing Cost	1000.00%	1000.00%
Commercial FHA Mortgage Loans \| Maximum
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Discount Rate	12.00%	13.00%
Commercial FHA Mortgage Loans \| Minimum
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Discount Rate	10.00%	10.00%
Residential mortgage loans
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Servicing Fee	0.26%	0.26%
Interest Rate	3.93%	3.89%
Remaining Years to Maturity	23 years 6 months	24 years 2 months 12 days
Prepayment Rate	10.89%	9.72%
Servicing Cost	58.00%	60.00%
Residential mortgage loans \| Maximum
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Discount Rate	11.00%	11.00%
Residential mortgage loans \| Minimum
Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value [Abstract]
Discount Rate	8.00%	9.00%

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

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- Definition

Servicing costs used to estimate the fair value of servicing assets and servicing liabilities.

+ References

No definition available.

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- Definition

Servicing fees used to estimate the fair value of servicing assets and servicing liabilities.

+ References

No definition available.

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- References

No definition available.

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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=68078379&loc=d3e122596-111746

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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- Definition

Weighted average life of financial assets and financial liabilities, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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