Note 13 - Fair Value - Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jan. 01, 2021		Dec. 31, 2020
Debt securities available for sale	$ 77,440	$ 83,358	[1]	$ 83,358	[2]
Interest receivable	8,146	$ 9,052	[3]	9,052	[2]
Derivative financial liabilities	1,022			1,131
Reported Value Measurement [Member]
Cash and cash equivalents	635,007			456,561
Debt securities available for sale	77,440			83,358
Equity securities	55			55
Loans held for investment, net of allowance	2,122,226			2,160,450
Interest receivable	8,146			9,052
Deferred compensation assets	4,901			4,181
Securities sold under agreements to repurchase	1,106			964
Interest payable	345			582
Derivative financial liabilities	1,022			4,181
Deferred compensation liabilities	4,901			1,131
Loans held for sale				0
FDIC indemnification asset				1,223
Reported Value Measurement [Member] | Bank Time Deposits [Member]
Deposits fair value	371,589			420,619
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	635,007			456,561
Debt securities available for sale	77,440			83,358
Equity securities	55			55
Loans held for investment, net of allowance	2,086,930			2,126,221
Interest receivable	8,146			9,052
Deferred compensation assets	4,901			4,181
Securities sold under agreements to repurchase	1,106			964
Interest payable	345			582
Derivative financial liabilities	1,022			4,181
Deferred compensation liabilities	4,901			1,131
Loans held for sale				0
FDIC indemnification asset				509
Estimate of Fair Value Measurement [Member] | Bank Time Deposits [Member]
Deposits fair value	370,567			423,120
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	635,007			456,561
Debt securities available for sale	0			0
Equity securities	0			0
Loans held for investment, net of allowance	0			0
Interest receivable	0			0
Deferred compensation assets	4,901			4,181
Securities sold under agreements to repurchase	0			0
Interest payable	0			0
Derivative financial liabilities	0			4,181
Deferred compensation liabilities	4,901			0
Loans held for sale				0
FDIC indemnification asset				0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 1 [Member] | Bank Time Deposits [Member]
Deposits fair value	0			0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0			0
Debt securities available for sale	77,440			83,358
Equity securities	55			55
Loans held for investment, net of allowance	0			0
Interest receivable	8,146			9,052
Deferred compensation assets	0			0
Securities sold under agreements to repurchase	1,106			964
Interest payable	345			582
Derivative financial liabilities	1,022			0
Deferred compensation liabilities	0			1,131
Loans held for sale				0
FDIC indemnification asset				0
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member] | Bank Time Deposits [Member]
Deposits fair value	370,567			423,120
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0			0
Debt securities available for sale	0			0
Equity securities	0			0
Loans held for investment, net of allowance	2,086,930			2,126,221
Interest receivable	0			0
Deferred compensation assets	0			0
Securities sold under agreements to repurchase	0			0
Interest payable	0			0
Derivative financial liabilities	0			0
Deferred compensation liabilities	0			0
Loans held for sale				0
FDIC indemnification asset				509
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member] | Bank Time Deposits [Member]
Deposits fair value	$ 0			$ 0

[1] Per our analysis no ACL was necessary for investment securities available-for-sale.

[2] Derived from audited financial statements

[3] Accrued interest receivable from acquired credit impaired loans of $57 thousand was reclassed to other assets and was offset by the reclass of the grossed up credit discount on acquired credit impaired loans of $57 thousand that was moved to the ACL for the purchased credit deteriorated loans.