Available-for-Sale Securities - Additional Information (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2020 USD ($) Security	Dec. 31, 2019 USD ($) Security
Investments Debt And Equity Securities [Abstract]
Held to maturity	$ 0	$ 0
Sale of available-for-sale securities	0	$ 0
Available-for-sale securities matured	17,288,000
Purchases of available-for-sale securities	10,113,000
Unrealized gain (loss) on securities	$ 0
Number of available for sale securities \| Security	7	10
Number of investment securities not other than temporary \| Security	0	9
Securities pledged	$ 0	$ 0

Available for sale securities purchase during the period.

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- Definition

Investment portfolio number of available for sale securities.

+ References

No definition available.

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- Definition

Sales of available for sale securities.

+ References

No definition available.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27290-111563

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- Definition

Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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- References

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- Definition

Amount of cash inflow from sale, maturity, prepayment and call of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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