Note 15 - Employee Benefit Plans - Deferred Compensation Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Balance, beginning	$ 19,474	$ 15,029	$ 12,347
Employee deferrals	3,959	2,474	1,407
Company match and interest	2,628	2,072	1,367
Cash payments made	(1,348)	(101)	(92)
Balance, ending	24,713	19,474	15,029
Supplemental Executive Retirement Plans [Member]
Balance, beginning	5,160	4,623	4,330
Company match and interest	1,193	701	457
Cash payments made	(164)	(164)	(164)
Balance, ending	$ 6,189	$ 5,160	$ 4,623

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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- Definition

Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement.

+ References

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- Definition

Amount of distribution made to individual in accordance with deferred compensation arrangement.

+ References

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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