Note 15 - Employee Benefit Plans - Deferred Compensation Agreements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance, beginning	$ 15,029	$ 12,347	$ 10,455
Employee deferrals	2,474	1,407	933
Company match and interest	2,072	1,367	1,025
Cash payments made	(101)	(92)	(66)
Balance, ending	19,474	15,029	12,347
Supplemental Executive Retirement Plans [Member]
Balance, beginning	4,623	4,330	4,093
Company match and interest	701	457	401
Cash payments made	(164)	(164)	(164)
Balance, ending	$ 5,160	$ 4,623	$ 4,330

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=116856206&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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