SECURITIES - Available-for-sale Major Categories (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Securities available-for-sale:
Amortized Cost	$ 1,093,686	$ 1,574,094
Gross Unrealized Gains	3	11,403
Gross Unrealized Losses	(85,932)	(21,786)
Fair Value	1,007,757	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	247,412	247,916
Gross Unrealized Losses	(15,532)	(3,147)
Fair Value	231,880	244,769
Corporate Securities
Securities available-for-sale:
Amortized Cost	151,335	148,430
Gross Unrealized Gains		4,354
Gross Unrealized Losses	(10,139)	(754)
Fair Value	141,196	152,030
Pass-through mortgage-backed securities ("MBS") issued by government sponsored entities ("GSEs")
Securities available-for-sale:
Amortized Cost	299,686	528,749
Gross Unrealized Gains	3	4,271
Gross Unrealized Losses	(22,047)	(6,566)
Fair Value	277,642	526,454
Agency collateralized mortgage obligations ("CMOs")
Securities available-for-sale:
Amortized Cost	357,546	527,348
Gross Unrealized Gains		2,705
Gross Unrealized Losses	(35,665)	(8,795)
Fair Value	321,881	521,258
State and municipal obligations.
Securities available-for-sale:
Amortized Cost	37,707	39,175
Gross Unrealized Gains		73
Gross Unrealized Losses	(2,549)	(302)
Fair Value	$ 35,158	$ 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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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).

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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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