Advances from Federal Home Loan Bank- Additional information (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Pledged Assets Separately Reported, Loans Pledged as Collateral, at Fair Value	$ 2,000,000,000.0	$ 1,200,000,000
Proceeds From First Federal Home Loan Bank Advances	1,400,000,000
Outstanding federal home loan bank advances	$ 0	$ 85,063,000
Residential Mortgage [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Percentage Of Advances Secured Collateral Pledged	128.00%
Commercial Real Estate [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Percentage Of Advances Secured Collateral Pledged	120.00%
Agriculture Real Estate Loans [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Percentage Of Advances Secured Collateral Pledged	123.00%

The percentage of advances secured and collateral.

No definition available.

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- Definition

The cash inflow associated with Federal Home Loan Bank Advances proceeds during the period.

+ References

No definition available.

+ Details

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The fair value, as of the date of each statement of financial position presented, of loans which are owned but transferred to serve as collateral for the payment of the related debt obligation primarily arising from secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

+ Details

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- Details

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- Details

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