NOTE 2 - INVESTMENT SECURITIES - Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities held to maturity:
Securities held to maturity, at amortized cost	$ 434,892	$ 400,646
Securities held to maturity, gross unrealized gains	26,292	26,042
Securities held to maturity, gross unrealized (losses)	(985)	(143)
Securities held to maturity, fair value	460,199	426,545
Securities available for sale:
Debt Securities, Available-for-sale, Amortized Cost	336,863	206,962
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	11,594	4,068
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(1,261)	(335)
Debt Securities, Available-for-sale	347,196	210,695
Municipal securities
Securities held to maturity:
Securities held to maturity, at amortized cost	433,842	399,596
Securities held to maturity, gross unrealized gains	26,292	26,042
Securities held to maturity, gross unrealized (losses)	(984)	(143)
Securities held to maturity, fair value	459,150	425,495
Securities available for sale:
Debt Securities, Available-for-sale, Amortized Cost	132,545	46,659
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,497	1,602
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(809)	(4)
Debt Securities, Available-for-sale	135,233	48,257
U.S. govt. sponsored agency securities
Securities available for sale:
Debt Securities, Available-for-sale, Amortized Cost	17,791	19,872
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	667	283
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(21)	(77)
Debt Securities, Available-for-sale	18,437	20,078
Residential mortgage-backed and related securities
Securities available for sale:
Debt Securities, Available-for-sale, Amortized Cost	128,281	118,724
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	6,158	2,045
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(292)	(182)
Debt Securities, Available-for-sale	134,147	120,587
Asset-backed securities
Securities available for sale:
Debt Securities, Available-for-sale, Amortized Cost	39,696	16,958
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,108
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(139)	(71)
Debt Securities, Available-for-sale	40,665	16,887
Other Securities
Securities held to maturity:
Securities held to maturity, at amortized cost	1,050	1,050
Securities held to maturity, gross unrealized (losses)	(1)
Securities held to maturity, fair value	1,049	1,050
Securities available for sale:
Debt Securities, Available-for-sale, Amortized Cost	18,550	4,749
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	164	138
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax		(1)
Debt Securities, Available-for-sale	$ 18,714	$ 4,886

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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