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Allowance for Credit Losses and Credit Quality of Loans (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020 | Mar. 31, 2020 | Dec. 31, 2019
Allowance for Credit Losses [Abstract] |  |  |  |
Allowance for credit losses | $ 105,000 | $ 110,000 | $ 100,000 | $ 75,999
Percentage of allowance of credit losses | 1.38% | 1.47% |  |
Retained earnings | $ 777,170 | $ 749,056 |  |
Loans purchased with credit deterioration | 0 | 0 |  |
Accrued Interest Receivable [Member] |  |  |  |
Allowance for Credit Losses [Abstract] |  |  |  |
Allowance for credit losses | 500 | 600 |  |
AIR on loans | $ 22,600 | 23,700 |  |
Write-off of uncollectible interest period | 120 days |  |  |
ASU 2016-13 [Member] | Loans [Member] |  |  |  |
Allowance for Credit Losses [Abstract] |  |  |  |
Allowance for credit losses |  |  |  | 3,000
Retained earnings |  |  |  | (2,300)
Deferred tax asset |  |  |  | 700
Consumer Loans [Member] |  |  |  |
Allowance for Credit Losses [Abstract] |  |  |  |
Allowance for credit losses | $ 34,580 | 37,803 | $ 37,546 | $ 32,122
Amount of loans purchased |  | $ 51,900 |  |
Discount on loans purchased |  | 1.00% |  |
Allowance for credit losses on loans purchased |  | $ 3,600 |  |

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- Definition Allowance for credit losses as a percentage of financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References No definition available. + Details
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- Definition The write-off period of uncollectible interest of delinquent loans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Amount of loans purchased with credit deterioration during the period. + References No definition available. + Details
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- Definition Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was 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=121585399&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 (b)(2) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + Details
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- Definition Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31931-109318 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120406818&loc=d3e31917-109318 + Details
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- Definition Amount, after allowance for credit loss, of accrued interest on financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL120267960-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL120267845-210446 + Details
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- Definition The cash outflow for the purchase of loan receivable arising from the financing of goods and services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585 + Details
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