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Summary of Significant Accounting Policies - Additional Information (Details) | 12 Months Ended
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Dec. 31, 2020 Segment
Finite Lived Intangible Assets [Line Items] |
Maximum maturity period for cash equivalents | 90 days
Number of investment portfolios | 3
Number of securities held as trading securities | 0
Useful lives of premises and equipment | three to forty years
Number of reportable segments | 2
Core Deposits [Member] |
Finite Lived Intangible Assets [Line Items] |
Finite-lived intangible asset, useful life | 7 years

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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
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