Loan Servicing - Key economic assumptions (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Loan Servicing
Fair value of servicing rights	$ 3,277	$ 3,845
Weighted average remaining term, years	20 years	20 years 1 month 6 days
Prepayment speeds	14.20%	11.80%
Discount rate	9.40%	9.40%

Weighted average life of securitized assets regardless of when the transfer occurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107314-111719

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- Definition

Discount rate which is used to value residual cash flows generated by financial assets of a securitization, asset-backed financing arrangement, or similar transfer regardless of when the transfer occurred.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118948506&loc=d3e107314-111719

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Balance Type:	na
Period Type:	duration

- Definition

Estimated rate of prepayment of principal on financial assets regardless of when the transfer occurred.

+ References

+ Details

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- References

No definition available.

+ Details

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- Definition

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7516967&loc=d3e66267-113978

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Balance Type:	debit
Period Type:	instant