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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - New Accounting Pronouncements (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2021	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' equity attributable to parent	$ (897,207)	$ (1,065,290)		$ (907,245)	$ (945,534)
Current	81,030	92,584	$ 57,649
Allowance for credit losses - unfunded loan commitments			4,064
Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current	84,213	98,189		61,713	66,814
Commercial \| Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			22,353
Commercial \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			5,941
Commercial \| Multifamily
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			11,405
Commercial \| SBA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			3,120
Commercial \| Construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			3,906
Consumer \| Single family residential mortgage
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			10,486
Consumer \| Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			438
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' equity attributable to parent	(110,179)	$ (147,894)		(127,733)	(140,952)
As Reported Under ASC 326
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			65,258
Allowance for credit losses - unfunded loan commitments			2,838
As Reported Under ASC 326 \| Commercial \| Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			23,015
As Reported Under ASC 326 \| Commercial \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			10,788
As Reported Under ASC 326 \| Commercial \| Multifamily
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			13,214
As Reported Under ASC 326 \| Commercial \| SBA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			3,508
As Reported Under ASC 326 \| Commercial \| Construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			4,009
As Reported Under ASC 326 \| Consumer \| Single family residential mortgage
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			10,066
As Reported Under ASC 326 \| Consumer \| Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			658
Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Transfer of loans to held-for-sale	6,400
Stockholders' equity attributable to parent				4,503
Current			7,609
Allowance for credit losses - unfunded loan commitments			(1,226)
Impact of ASC 326 Adoption \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current	0			6,383	$ 0
Impact of ASC 326 Adoption \| Commercial \| Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			662
Impact of ASC 326 Adoption \| Commercial \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			4,847
Impact of ASC 326 Adoption \| Commercial \| Multifamily
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			1,809
Impact of ASC 326 Adoption \| Commercial \| SBA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			388
Impact of ASC 326 Adoption \| Commercial \| Construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			103
Impact of ASC 326 Adoption \| Consumer \| Single family residential mortgage
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			(420)
Impact of ASC 326 Adoption \| Consumer \| Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Current			$ 220
Impact of ASC 326 Adoption \| Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Stockholders' equity attributable to parent	$ 4,500			$ 4,503