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Loans, Balance in Allowance for Loan and Lease Losses and Recorded Investment in Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | $ 35,096 | [1] | $ 35,096 | [1] | $ 35,908 |  |
Provision charged to expense |  |  |  |  |  | 4,819 |  |
Losses charged off |  |  |  |  |  | (9,736) |  |
Recoveries |  |  |  |  |  | 4,105 |  |
Ending balance |  |  |  | $ 48,022 | [1] | 35,096 | [1] | $ 35,908
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 1,212 |  |
Collectively evaluated for impairment |  |  |  |  |  | 33,884 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 57,771 |  |
Collectively evaluated for impairment |  |  |  |  |  | 3,190,893 |  |
Period of reasonable and supportable forecast |  |  |  | 12 months |  |  |  |
Provision for credit losses | [2] |  |  | $ 16,047 |  | 4,819 |  | 6,167
Increase (decrease) in allowance for credit losses |  |  |  | 11,200 |  |  |  |
Allowance for credit losses |  |  |  | $ 48,022 |  | $ 35,096 |  |
Allowance for credit losses to nonperforming loans |  |  |  | 180.70% |  |  |  |
Allowance for loan and lease losses to nonperforming loans |  |  |  |  |  | 104.40% |  |
Credit loss reserve as percentage of total loans outstanding |  |  |  | 1.35% |  |  |  |
Allowance for loan loss as percentage of total loans outstanding |  |  |  |  |  | 1.08% |  |
Real Estate Mortgage [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 5,501 |  | $ 5,501 |  |  |  |
Ending balance |  |  |  |  |  | $ 5,501 |  |
Consumer Direct [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 1,711 |  | 1,711 |  |  |  |
Ending balance |  |  |  |  |  | 1,711 |  |
Consumer Indirect [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 6,201 |  | 6,201 |  |  |  |
Ending balance |  |  |  |  |  | 6,201 |  |
Commercial [Member] | Construction [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 1,299 |  | 1,299 |  | 862 |  |
Provision charged to expense |  |  |  |  |  | 497 |  |
Losses charged off |  |  |  |  |  | (72) |  |
Recoveries |  |  |  |  |  | 12 |  |
Ending balance |  |  |  |  |  | 1,299 |  | 862
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 99 |  |
Collectively evaluated for impairment |  |  |  |  |  | 1,200 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 3,010 |  |
Collectively evaluated for impairment |  |  |  |  |  | 101,799 |  |
Commercial [Member] | Real Estate Mortgage [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 14,025 |  | 14,025 |  | 14,531 |  |
Provision charged to expense |  |  |  |  |  | (137) |  |
Losses charged off |  |  |  |  |  | (727) |  |
Recoveries |  |  |  |  |  | 358 |  |
Ending balance |  |  |  |  |  | 14,025 |  | 14,531
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 227 |  |
Collectively evaluated for impairment |  |  |  |  |  | 13,798 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 41,379 |  |
Collectively evaluated for impairment |  |  |  |  |  | 1,128,596 |  |
Commercial [Member] | Equipment Lease Financing [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 4 |  | 4 |  | 12 |  |
Provision charged to expense |  |  |  |  |  | (8) |  |
Losses charged off |  |  |  |  |  | 0 |  |
Recoveries |  |  |  |  |  | 0 |  |
Ending balance |  |  |  |  |  | 4 |  | 12
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 4 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 481 |  |
Commercial [Member] | Commercial Other [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 6,355 |  | 6,355 |  | 4,993 |  |
Provision charged to expense |  |  |  |  |  | 3,032 |  |
Losses charged off |  |  |  |  |  | (2,179) |  |
Recoveries |  |  |  |  |  | 509 |  |
Ending balance |  |  |  |  |  | 6,355 |  | 4,993
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 886 |  |
Collectively evaluated for impairment |  |  |  |  |  | 5,469 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 11,073 |  |
Collectively evaluated for impairment |  |  |  |  |  | 378,610 |  |
Residential [Member] | Construction [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 372 |  | 372 |  | 512 |  |
Provision charged to expense |  |  |  |  |  | (40) |  |
Losses charged off |  |  |  |  |  | (100) |  |
Recoveries |  |  |  |  |  | 0 |  |
Ending balance |  |  |  |  |  | 372 |  | 512
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 372 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 63,350 |  |
Residential [Member] | Real Estate Mortgage [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 4,232 |  | 4,232 |  | 4,433 |  |
Provision charged to expense |  |  |  |  |  | 414 |  |
Losses charged off |  |  |  |  |  | (767) |  |
Recoveries |  |  |  |  |  | 152 |  |
Ending balance |  |  |  |  |  | 4,232 |  | 4,433
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 4,232 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 2,309 |  |
Collectively evaluated for impairment |  |  |  |  |  | 730,694 |  |
Provision for credit losses |  |  |  | 1,584 |  |  |  |
Allowance for credit losses |  |  |  | 7,832 |  | 4,604 |  |
Residential [Member] | Home Equity Lines [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 897 |  | 897 |  | 841 |  |
Provision charged to expense |  |  |  |  |  | 172 |  |
Losses charged off |  |  |  |  |  | (139) |  |
Recoveries |  |  |  |  |  | 23 |  |
Ending balance |  |  |  |  |  | 897 |  | 841
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 897 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 111,894 |  |
Provision for credit losses |  |  |  | 16 |  |  |  |
Allowance for credit losses |  |  |  | 844 |  | 897 |  |
Consumer [Member] | Consumer Direct [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 1,711 |  | 1,711 |  | 1,883 |  |
Provision charged to expense |  |  |  |  |  | 528 |  |
Losses charged off |  |  |  |  |  | (1,100) |  |
Recoveries |  |  |  |  |  | 400 |  |
Ending balance |  |  |  |  |  | 1,711 |  | 1,883
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 1,711 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 148,051 |  |
Provision for credit losses |  |  |  | 609 |  |  |  |
Allowance for credit losses |  |  |  | 1,863 |  | 1,711 |  |
Consumer [Member] | Consumer Indirect [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 6,201 |  | 6,201 |  | 7,841 |  |
Provision charged to expense |  |  |  |  |  | 361 |  |
Losses charged off |  |  |  |  |  | (4,652) |  |
Recoveries |  |  |  |  |  | 2,651 |  |
Ending balance |  |  |  |  |  | 6,201 |  | $ 7,841
Ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 6,201 |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Individually evaluated for impairment |  |  |  |  |  | 0 |  |
Collectively evaluated for impairment |  |  |  |  |  | 527,418 |  |
Provision for credit losses |  |  |  | 4,079 |  |  |  |
Allowance for credit losses |  |  |  | 9,906 |  | 6,201 |  |
ASU 2016-13 [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 38,137 |  | 38,137 |  |  |  |
Ending balance |  |  |  |  |  | 38,137 |  |
ASU 2016-13 [Member] | Inherent Model Risk [Member] |  |  |  |  |  |  |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Increase (decrease) in allowance for credit loss balance |  | (1,600) |  |  |  |  |  |
ASU 2016-13 [Member] | Real Estate Mortgage [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 7,319 |  | 7,319 |  |  |  |
Ending balance |  |  |  |  |  | 7,319 |  |
ASU 2016-13 [Member] | Consumer Direct [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | 1,671 |  | 1,671 |  |  |  |
Ending balance |  |  |  |  |  | 1,671 |  |
ASU 2016-13 [Member] | Consumer Indirect [Member] |  |  |  |  |  |  |  |
Allowance for loan losses [Roll Forward] |  |  |  |  |  |  |  |
Beginning balance |  | $ 7,467 |  | $ 7,467 |  |  |  |
Ending balance |  |  |  |  |  | 7,467 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2016-13 [Member] |  |  |  |  |  |  |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  |  |  |  | 3,040 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2016-13 [Member] | Residential [Member] | Real Estate Mortgage [Member] |  |  |  |  |  |  |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  |  |  |  | 1,893 |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2016-13 [Member] | Residential [Member] | Home Equity Lines [Member] |  |  |  |  |  |  |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  |  |  |  | (75) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2016-13 [Member] | Consumer [Member] | Consumer Direct [Member] |  |  |  |  |  |  |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  |  |  |  | (40) |  |
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASU 2016-13 [Member] | Consumer [Member] | Consumer Indirect [Member] |  |  |  |  |  |  |  |
Loans ending balance [Abstract] |  |  |  |  |  |  |  |
Allowance for credit losses |  |  |  |  |  | $ 1,265 |  |
[1] | Effective January 1, 2020, the allowance for loan and lease losses became the allowance for credit losses with the implementation of ASU 2016-13, commonly referred to as CECL.
[2] | Effective January 1, 2020, the provision for loan losses became the provision for credit losses with the implementation of ASU 2016-13, commonly referred to as CECL.

X
- Definition The credit loss reserve (allowance for credit loss) as a percentage of total loans outstanding. + References No definition available. + Details
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- Definition The allowance for credit losses as a percentage of nonperforming loans. + References No definition available. + Details
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- Definition The allowance for loan and lease losses as a percentage of nonperforming loans. + References No definition available. + Details
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- Definition The credit loss reserve (allowance for loan loss) as a percentage of total loans outstanding. + References No definition available. + Details
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- Definition Increase (decrease) in the amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References No definition available. + Details
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- References No definition available. + Details
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- Definition Period of reasonable and supportable forecast used in determining allowance for credit losses, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter. + References No definition available. + Details
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- Definition Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(4) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
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- Definition The balance of financing receivables that were collectively evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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- Definition The balance of financing receivables that were individually evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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