Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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

No definition available.

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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- Definition

Value of input used to measure servicing asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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Fair Value Measurements - Quantitative and Qualitative Information (Details) $ in Thousands	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2018 USD ($)
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	$ 6,715	$ 7,357
Securities available-for-sale, at fair value	509,090	541,248	$ 509,090
Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Mortgage servicing rights, fair value	6,715	7,357
Securities available-for-sale, at fair value	19,556	8,165	26,500
US States and Political Subdivisions Debt Securities [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	281,172	274,067
US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	19,600
Collateralized Mortgage Obligations [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value	$ 64,330	$ 64,429
Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value			$ 2,100
Measurement Input, Discount Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		10.2
Measurement Input, Discount Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member] \| Minimum [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	10.0	10.0
Measurement Input, Discount Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member] \| Maximum [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	17.0	229.7
Measurement Input, Discount Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member] \| Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	10.1
Measurement Input, Constant Prepayment Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input		9.6
Measurement Input, Constant Prepayment Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member] \| Minimum [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	7.0	7.0
Measurement Input, Constant Prepayment Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member] \| Maximum [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	69.0	68.9
Measurement Input, Constant Prepayment Rate \| Mortgage Servicing Rights [Member] \| Fair Value, Inputs, Level 3 [Member] \| Weighted Average [Member]
Quantitative information about Level 3 fair value measurements
Servicing Asset, Measurement Input	11.5
Fair Value, Measurements, Recurring [Member]
Quantitative information about Level 3 fair value measurements
Securities available-for-sale, at fair value		$ 10,951