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Fair Value Measurements - Quantitative and Qualitative Information (Details) - USD ($) | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | $ 7,357,000 | $ 6,944,000
Securities available-for-sale, at fair value | 541,248,000 | 541,439,000
Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 8,165,000 | 16,529,000
States and political subdivisions |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 274,067,000 | 278,092,000
Collateralized mortgage obligations |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 64,429,000 | 65,939,000
Recurring |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | 7,357,000 | 6,944,000
Recurring | Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | 7,357,000 | 6,944,000
Recurring | States and political subdivisions |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 274,067,000 | 278,092,000
Recurring | States and political subdivisions | Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 8,165,000 | 14,261,000
Recurring | Collateralized mortgage obligations |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value | 64,429,000 | 65,939,000
Recurring | Collateralized mortgage obligations | Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Securities available-for-sale, at fair value |  | 2,268,000
Recurring | Measurement Input, Discount Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 |  |
Quantitative information about Level 3 fair value measurements |  |
Mortgage servicing rights, fair value | $ 7,357,000 | $ 6,944,000
Recurring | Measurement Input, Discount Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 10.0 | 10.0
Recurring | Measurement Input, Discount Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 229.7 | 34.3
Recurring | Measurement Input, Discount Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 10.2 | 10.2
Recurring | Measurement Input, Constant Prepayment Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 | Minimum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 7.0 | 7.0
Recurring | Measurement Input, Constant Prepayment Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 | Maximum |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 68.9 | 68.4
Recurring | Measurement Input, Constant Prepayment Rate | Mortgage servicing rights | Discounted Cash Flow | Level 3 | Weighted Average |  |
Quantitative information about Level 3 fair value measurements |  |
Servicing Asset, Measurement Input | 9.6 | 9.6

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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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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