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Loans - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Receivables [Abstract] |  |  |  |  |
Impaired Financing Receivable, Interest Income, Accrual Method |  |  | $ 0 |  |
Impaired Financing Receivable, Recorded Investment | $ 65,900,000 |  | 65,900,000 |  | $ 64,700,000
Impaired Financing Receivable, Related Allowance |  |  |  |  | 3,600,000
Loans renegotiated in troubled debt restructurings | 20,000,000.0 |  | 20,000,000.0 |  | 24,900,000
Troubled restructurings included in non-accrual loans | 16,800,000 |  | 16,800,000 |  | 19,400,000
Loans renegotiated in troubled debt restructurings, accrual loans | 3,200,000 |  | 3,200,000 |  | 5,500,000
Troubled debt restructurings | 0 |  | 0 |  |
Charge-offs directly related to modifying troubled debt restructurings | 0 |  |  |  |
Balance of defaulted loans under trouble debt restructurings | 0 |  | 0 |  |
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend |  |  |  |  | $ 0
Loans and Leases Receivable, Commitments to Purchase or Sell | 0 | $ 0 | 0 | $ 0 |
Proceeds from Sale of Loans Held-for-investment | $ 0 | $ 0 | $ 0 | $ 0 |

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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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- Definition Amount of financing receivable modified as troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554 + Details
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- Definition Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524 + Details
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- Definition Reflects the amount of the write-down related to a troubled debt restructuring. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554 + Details
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- Definition Reflects the carrying amount of loans and leases for which agreements to acquire or dispose exist. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 825 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61044-112788 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 825 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61082-112788 + Details
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- Definition The cash inflow from Sales of Loans Held For Investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585 + Details
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