Loans - Additional Information (Details)	12 Months Ended
Dec. 31, 2019 USD ($) Contract	Dec. 31, 2018 USD ($) Contract	Dec. 31, 2017 USD ($) Contract
Accounts Notes Loans And Financing Receivable Gross Allowance And Net [Abstract]
Loans	$ 0	$ 0
Accrued interest receivable	2,900,000	2,800,000
Recorded investment in troubled debt restructurings	333,000	343,000
Specific reserves to customers whose loan terms have been modified in troubled debt restructurings	$ 333,000	$ 343,000
Loans identified as trouble debt restructurings \| Contract	0	0	0
Financing receivable, modifications, subsequent default, recorded investment	$ 0	$ 0	$ 0

Allowance for credit losses change in method of calculating impairments.

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- Definition

Impaired financing receivable, accrued interest receivable.

+ References

No definition available.

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- References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ 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=118936363&loc=SL6953676-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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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=118936363&loc=SL6953682-111524

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(e))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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