Note 3 - Investment Securities - Interest Income From Investment Securities (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Taxable	$ 18,773	$ 15,598	$ 37,406	$ 30,547
Tax-exempt from regular federal income tax	4,073	5,027	8,388	9,888
Total interest income from investment securities	$ 22,846	$ 20,625	$ 45,794	$ 40,435

Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

No definition available.

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.2)
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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- Definition

Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

+ References

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