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Loans and Allowance for Loan Losses - Purchased Credit-Impaired (Details) $ in Thousands | 3 Months Ended | 9 Months Ended | 81 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2018 USD ($) | Nov. 21, 2017 acquisition | Dec. 31, 2018 USD ($)
Business Acquisitions, Purchased Credit-Impaired Loans [Line Items] |  |  |  |  |  |
Number of banks acquired | acquisition |  |  |  |  | 3 |
Accretable Yield [Roll Forward] |  |  |  |  |  |
Balance at beginning of period | $ 819 | $ 1,059 | $ 934 | $ 1,254 |  |
Accretion | (55) | (63) | (170) | (258) |  |
Balance at end of period | 764 | $ 996 | 764 | $ 996 |  |
Purchased credit-impaired |  |  |  |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |  |  |  |
Unpaid Principal Balance | 2,459 |  | 2,459 |  |  | $ 2,579
Carrying Value | 2,059 |  | 2,059 |  |  | 2,112
Purchased credit-impaired | Commercial loans | Commercial and industrial |  |  |  |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |  |  |  |
Unpaid Principal Balance | 48 |  | 48 |  |  | 89
Carrying Value | 4 |  | 4 |  |  | 31
Purchased credit-impaired | Commercial real estate loans | Commercial real estate, owner-occupied |  |  |  |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |  |  |  |
Unpaid Principal Balance | 1,208 |  | 1,208 |  |  | 1,247
Carrying Value | 1,153 |  | 1,153 |  |  | 1,187
Purchased credit-impaired | Commercial real estate loans | Commercial real estate, investor |  |  |  |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |  |  |  |
Unpaid Principal Balance | 1,009 |  | 1,009 |  |  | 1,033
Carrying Value | 828 |  | 828 |  |  | 811
Purchased credit-impaired | Residential loans | Home equity |  |  |  |  |  |
PCI Loans, Carrying Value [Abstract] |  |  |  |  |  |
Unpaid Principal Balance | 194 |  | 194 |  |  | 210
Carrying Value | $ 74 |  | $ 74 |  |  | $ 83

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- Definition Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 + Details
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- Definition The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538 + Details
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- Definition The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544 + Details
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