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SECURITIES - Summary of AFS Securities Portfolio (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	$ 262,624		$ 1,198,562
Gross Unrealized gains	461		9,473
Gross Unrealized losses	(11,589)		(6,258)
Allowance for credit losses - investments	(11,226)	$ (10,743)	(10,399)	$ (7,245)
Estimated Fair Value	240,270		1,191,378
Collateralized mortgage obligations
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	10,941		13,862
Gross Unrealized losses	(936)		(37)
Estimated Fair Value	10,005		13,825
Agency Mortgage-backed Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	9,530		928,546
Gross Unrealized gains			6,563
Gross Unrealized losses	(530)		(6,120)
Estimated Fair Value	9,000		928,989
Beneficial interest - FHLMC securitizations
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	20,015		21,606
Gross Unrealized gains	201		373
Allowance for credit losses - investments	(11,226)		(10,399)
Estimated Fair Value	8,990		11,580
Municipal bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	50,567		52,052
Gross Unrealized gains			94
Gross Unrealized losses	(3,733)
Estimated Fair Value	46,834		52,146
Corporate Bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	147,635		154,027
Gross Unrealized gains	191		2,441
Gross Unrealized losses	(6,327)		(92)
Estimated Fair Value	141,499		156,376
U.S. Treasury
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	897		499
Gross Unrealized losses	(60)		(9)
Estimated Fair Value	837		490
SBA securities
Schedule Of Available For Sale Securities [Line Items]
Amortized cost	23,039		27,970
Gross Unrealized gains	69		2
Gross Unrealized losses	(3)
Estimated Fair Value	$ 23,105		$ 27,972