Federal Home Loan Bank and Federal Reserve Bank Stocks (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Banks [Abstract]
FHLB stock, at cost	$ 196,457,000	$ 318,473,000
FRB stock, at cost	123,979,000	123,967,000
Total investments	320,436,000	442,440,000
Impairment charges on investments	$ 0	$ 0	$ 0

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

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- Definition

Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

+ References

No definition available.

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- References

No definition available.

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- Definition

Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562

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