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Loans - Schedule of Loans Renegotiated in Troubled Debt Restructurings (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Dec. 31, 2017
Loans and Leases Receivable, Troubled Debt Restructuring [Line Items] |  |  |
Loans renegotiated in troubled debt restructurings | $ 34,900,000 |  | $ 44,500,000
Loans renegotiated in troubled debt restructurings, non-accrual loans | 28,000,000 |  | 31,900,000
Loans renegotiated in troubled debt restructurings, accrual loans | 6,900,000 |  | $ 12,600,000
Loans restructured during period | 0 |  |
Charge-offs directly related to modifying troubled debt restructurings | 0 | $ 0 |
Balance of defaulted loans under trouble debt restructurings | 0 |  |
Commitments to lend additional funds | $ 0 |  |

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- Definition Pre-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details
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- Definition The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details
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- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details
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