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Loans and Allowance for Credit Losses on Loans - TDR (Details) | 12 Months Ended
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Dec. 31, 2020 USD ($) contract | Dec. 31, 2019 USD ($) contract
Troubled debt restructurings - modified during the period |  |
# of contracts | contract | 3 | 7
Pre-modification balance | $ 410,000 | $ 2,076,000
Post-modification balance | 395,000 | 1,949,000
Other information |  |
Commitments to lend to borrowers whose loans were classified as impaired | 0 | $ 0
Financing receivable, purchase | 0 |
Financing receivable, sales | $ 0 |
Residential Owner Occupied Loan [Member] | Home Affordable Modification Program [Member] |  |
Troubled debt restructurings - modified during the period |  |
# of contracts | contract | 3 | 3
Pre-modification balance | $ 410,000 | $ 399,000
Post-modification balance | 395,000 | $ 293,000
Commercial real estate - Investor | Others [Member] |  |
Troubled debt restructurings - modified during the period |  |
# of contracts | contract |  | 2
Pre-modification balance |  | $ 1,217,000
Post-modification balance |  | $ 1,200,000
Commercial real estate - Owner occupied | Deferral [Member] |  |
Troubled debt restructurings - modified during the period |  |
# of contracts | contract |  | 1
Pre-modification balance |  | $ 421,000
Post-modification balance |  | $ 418,000
HELOC | Others [Member] |  |
Troubled debt restructurings - modified during the period |  |
# of contracts | contract |  | 1
Pre-modification balance |  | $ 39,000
Post-modification balance |  | 38,000
TDR's defaulted |  |
Pre-modification outstanding recorded investment during the period | $ 0 | $ 39,000

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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 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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