Goodwill and Other Intangibles and Mortgage Servicing Rights - Mortgage servicing rights (Details) - Mortgage Servicing Rights - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Mortgage servicing rights (MSR) asset:
MSR asset at beginning of year	$ 3,749	$ 3,187
Capitalized MSR	1,807	1,203
Amortization during the period	(611)	(641)
MSR asset at end of period	4,945	3,749
Fair value of MSR asset at end of period	6,960	6,347
Residential mortgage loans serviced for others	$ 721,569	$ 603,446
Net book value of MSR asset to loans serviced for others	0.69%	0.62%

Represents Net book value of MSR asset to loans serviced for others.

No definition available.

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- Definition

Represents information of Residential mortgage loans serviced for others.

+ References

No definition available.

+ Details

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- Definition

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122739-111746

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- Definition

Amortized amount 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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

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Balance Type:	debit
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- Definition

Amount of additions from purchases, assumption or transfer to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

+ Details

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

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-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

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

+ References

No definition available.

+ Details

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- Details

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