NOTE 2 - INVESTMENT SECURITIES (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) state item	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) state item
Number of securities	581
Available-for-sale, unrealized loss positions, qualitative disclosure, number of positions	53
Aggregate losses of securities (as a percent)	0.80%
Available-for-sale, unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year	5
Other than temporary impairment losses, investments \| $	$ 0	$ 0
Number Of Charters Owning Municipal Securities	4
Municipal securities \| General Obligation Bonds
Number of issuers	91		93
Other investments \| $	$ 74,400		$ 77,200
Number of states holding investments \| state	21		22
Municipal securities \| General Obligation Bonds \| Minimum
Other investments \| $	$ 5,000		$ 5,000
Municipal securities \| General Obligation Bonds \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of states holding investments \| state	6		6
Municipal securities \| Revenue Bonds
Number of issuers	162		154
Other investments \| $	$ 438,400		$ 396,600
Number of states holding investments	18		17
Municipal securities \| Revenue Bonds \| Minimum
Other investments \| $	$ 5,000		$ 5,000
Municipal securities \| Revenue Bonds \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of states holding investments	7		9

The aggregate depreciation from amortized cost basis as a percent.

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- Definition

The number of the company's that own the company's municipal securities.

+ References

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Number of issuers of debt securities.

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Number of securities.

+ References

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- Definition

Represents the number of states investments are held in.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
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-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=118955579&loc=SL82922888-210455

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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