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Allowance for Loan Losses - Additional Information (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Loans considered nonperforming (in days) | 90 days |  |
Threshold for evaluation for impairment of substandard and nonaccrual commercial loans | $ 500 |  |
Change-off arising from participation loan agreement | 5,236 | $ (184) |
Commercial and industrial |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Change-off arising from participation loan agreement | 5,060 | $ 712 |
Commercial | Substandard |  |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |  |
Decrease in substandard loans resulted in loans downgraded | 15,900 |  |
Substandard loans | $ 165,300 |  | $ 181,200

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- Definition Minimum amount over which evaluation for impairment of substandard and nonaccrual commercial loans are made. + References No definition available. + Details
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- Definition Period interest and principal of loan due treated as loans considered nonperforming. + References No definition available. + Details
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- Definition Amount, after recoveries, of loans and leases that have been written-off. + References No definition available. + Details
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- Definition The increase (decrease) during the reporting period in outstanding loans including accrued interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585 + Details
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- Definition Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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