NOTE 2 - INVESTMENT SECURITIES (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) state item	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) state item
Number of securities \| item	606
Available-for-sale, unrealized loss positions, qualitative disclosure, number of positions \| item	182
Aggregate losses of securities (as a percent)	0.40%
Available-for-sale, unrealized loss positions, qualitative disclosure, number of positions, greater than or equal to one year \| item	170
Other than temporary impairment losses, investments \| $	$ 0	$ 0
Sale of securities \| $	$ 0	$ 0
Number Of Charters Owning Municipal Securities \| item	5
Municipal Bonds \| General Obligation Bonds
Number of issuers \| item	106		110
Other investments \| $	$ 86,000		$ 86,400
Number of states holding investments \| state	25		26
Municipal Bonds \| General Obligation Bonds \| Minimum
Other investments \| $	$ 5,000		$ 5,000
Municipal Bonds \| General Obligation Bonds \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of states holding investments \| state	6		6
Municipal Bonds \| Revenue Bonds
Number of issuers \| item	161		160
Other investments \| $	$ 375,400		$ 371,900
Number of states holding investments	19		19
Municipal Bonds \| Revenue Bonds \| Minimum
Other investments \| $	$ 5,000		$ 5,000
Municipal Bonds \| Revenue Bonds \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of states holding investments	7		7

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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- Definition

Number of issuers of debt securities.

+ References

No definition available.

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- Definition

Number of securities.

+ References

No definition available.

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- Definition

Represents the number of states investments are held in.

+ References

No definition available.

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

+ References

No definition available.

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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=109979856&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=99377789&loc=d3e19207-110258

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- Definition

The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

+ References

No definition available.

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