Note 11 - FHLB Advances and Other Borrowings (Details Textual) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Aug. 06, 2024	Dec. 31, 2023
Advance from Federal Home Loan Bank	$ 325			$ 200
Proceeds from FHLBank Advance, Investing Activities	2,500	$ 2,150
Payments of FHLBank Borrowings, Financing Activities	2,400	1,900
Proceeds from FHLBank Advance, Investing Activities, Net of Short Term Maturities	725	700
Payments of FHLBank Borrowings, Financing Activities, Net of Short Term Maturities	600	$ 400
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	1,210			1,330
Correspondent Banks [Member]
Federal Funds Corresponding Banks Maximum Amount Available	80			$ 80
Three Month Advance Maturing November 2024 [Member]
Advance from Federal Home Loan Bank	300		$ 100
Cash Overnight Advance [Member]
Advance from Federal Home Loan Bank	$ 25

The maximum amount available to draw of federal funds from corresponding banks.

No definition available.

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- Definition

Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity, net of maturities of 90 days or less.

+ References

No definition available.

+ Details

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- Definition

Amount of cash inflow from collection of advance by Federal Home Loan Bank (FHLBank), classified as investing activity, net of advances with maturities of 90 days or less.

+ References

No definition available.

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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
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478878/942-470-45-1

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- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478878/942-470-45-1

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- Definition

Amount of cash inflow from collection of advance by Federal Home Loan Bank (FHLBank), classified as investing activity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-12

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- Definition

Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

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