Note 14 - Disclosure of Financial Instruments Not Reported at Fair Value - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Cash and cash equivalents	$ 751,691	$ 961,192
Accrued interest receivable	15,690	13,745
Non-interest bearing	2,089,072	1,755,754
Time deposits	546,178	434,222
Accrued interest payable	337	300
Reported Value Measurement [Member]
Cash and cash equivalents	751,691	961,192
HTM debt securities	548,191
Federal Home Loan Bank stock	13,811	9,376
Loans, net	4,780,616	4,115,405
Accrued interest receivable	15,690	13,745
Non-interest bearing	2,089,072	1,755,754
Transaction deposits	4,110,241	3,597,538
Time deposits	546,178	434,222
Securities sold under agreement to repurchase	142,146	75,466
Federal funds purchased	8,920	10,374
Subordinated debentures	26,045
Accrued interest payable	337	300
Mortgage loans held for sale		8,614
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	751,691	961,192
HTM debt securities	535,807
Federal Home Loan Bank stock	13,811	9,376
Loans, net	4,719,799	4,129,091
Accrued interest receivable	15,690	13,745
Non-interest bearing	2,089,072	1,755,754
Transaction deposits	4,110,241	3,597,538
Time deposits	540,374	433,813
Securities sold under agreement to repurchase	142,146	75,466
Federal funds purchased	8,920	10,374
Subordinated debentures	26,226
Accrued interest payable	337	300
Mortgage loans held for sale		8,818
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	751,691	961,192
HTM debt securities	0
Federal Home Loan Bank stock	0	0
Loans, net	0	0
Accrued interest receivable	15,690	13,745
Non-interest bearing	2,089,072	1,755,754
Transaction deposits	0	0
Time deposits	0	0
Securities sold under agreement to repurchase	0	0
Federal funds purchased	0	0
Subordinated debentures	0
Accrued interest payable	337	300
Mortgage loans held for sale		0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
HTM debt securities	535,807
Federal Home Loan Bank stock	13,811	9,376
Loans, net	0	0
Accrued interest receivable	0	0
Non-interest bearing	0	0
Transaction deposits	4,110,241	3,597,538
Time deposits	540,374	433,813
Securities sold under agreement to repurchase	142,146	75,466
Federal funds purchased	8,920	10,374
Subordinated debentures	26,226
Accrued interest payable	0	0
Mortgage loans held for sale		8,818
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
HTM debt securities	0
Federal Home Loan Bank stock	0	0
Loans, net	4,719,799	4,129,091
Accrued interest receivable	0	0
Non-interest bearing	0	0
Transaction deposits	0	0
Time deposits	0	0
Securities sold under agreement to repurchase	0	0
Federal funds purchased	0	0
Subordinated debentures	0
Accrued interest payable	$ 0	0
Mortgage loans held for sale		$ 0

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

No definition available.

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- Definition

Represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount shown on the entity's books for investments made in Federal Home Loan Bank stock and other securities.

+ References

No definition available.

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- Definition

Fair value portion of transaction deposit liabilities held by the entity.

+ References

No definition available.

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- Definition

The sum of cash and cash equivalents plus Federal Funds Sold. Cash and cash equivalents consist of short term, highly liquid investments that are readily convertible to known amounts of cash and are so near their maturity that they present negligible risk of changes in value due to changes in interest rates -- usually with an original maturity less than 90 days.

+ References

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- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

Fair value portion of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

+ References

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- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3)(a)(4))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI https://asc.fasb.org/subtopic&trid=2196772

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- Definition

Fair value portion of mortgage loans held-for-sale.

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- Definition

The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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Amount of time deposit liabilities, including certificates of deposit.

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