SECURITIES - Available-for-sale Major Categories (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available-for-sale:
Amortized Cost	$ 1,350,740	$ 1,574,094
Gross Unrealized Gains	1,894	11,403
Gross Unrealized Losses	(75,598)	(21,786)
Fair Value	1,277,036	1,563,711
Agency Notes
Securities available-for-sale:
Amortized Cost		82,476
Gross Unrealized Losses		(2,222)
Fair Value		80,254
Treasury Securities
Securities available-for-sale:
Amortized Cost	247,665	247,916
Gross Unrealized Losses	(13,134)	(3,147)
Fair Value	234,531	244,769
Corporate Securities
Securities available-for-sale:
Amortized Cost	151,382	148,430
Gross Unrealized Gains	980	4,354
Gross Unrealized Losses	(4,937)	(754)
Fair Value	147,425	152,030
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs")
Securities available-for-sale:
Amortized Cost	443,266	528,749
Gross Unrealized Gains	905	4,271
Gross Unrealized Losses	(26,055)	(6,566)
Fair Value	418,116	526,454
Agency collateralized mortgage obligations ("CMOs")
Securities available-for-sale:
Amortized Cost	469,808	527,348
Gross Unrealized Gains	7	2,705
Gross Unrealized Losses	(29,632)	(8,795)
Fair Value	440,183	521,258
State and municipal obligations.
Securities available-for-sale:
Amortized Cost	38,619	39,175
Gross Unrealized Gains	2	73
Gross Unrealized Losses	(1,840)	(302)
Fair Value	$ 36,781	$ 38,946

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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-Section 50
-Paragraph 2
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Amount, before tax, of unrealized loss 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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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and 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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