Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Impact of Adopting ASU 2016-13 (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net decrease in retained earnings	$ 4,503	$ 4,503		$ 0
Allowance for credit losses - loans	78,243	57,649	$ 57,649
Allowance for credit losses - unfunded loan commitments		4,064
Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans	82,131		61,713	$ 68,093	$ 66,814
Unfunded Loan Commitment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans	$ 3,900		4,100
Commercial \| Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		22,353
Commercial \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		5,941
Commercial \| Multifamily
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		11,405
Commercial \| SBA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		3,120
Commercial \| Construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		3,906
Consumer \| Single family residential mortgage
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		10,486
Consumer \| Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		438
As Reported Under ASC 326
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		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]
Allowance for credit losses - loans		23,015
As Reported Under ASC 326 \| Commercial \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		10,788
As Reported Under ASC 326 \| Commercial \| Multifamily
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		13,214
As Reported Under ASC 326 \| Commercial \| SBA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		3,508
As Reported Under ASC 326 \| Commercial \| Construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		4,009
As Reported Under ASC 326 \| Consumer \| Single family residential mortgage
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		10,066
As Reported Under ASC 326 \| Consumer \| Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		658
Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		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]
Allowance for credit losses - loans			$ 6,383		$ 0
Impact of ASC 326 Adoption \| Commercial \| Commercial and industrial
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		662
Impact of ASC 326 Adoption \| Commercial \| Commercial real estate
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		4,847
Impact of ASC 326 Adoption \| Commercial \| Multifamily
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		1,809
Impact of ASC 326 Adoption \| Commercial \| SBA
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		388
Impact of ASC 326 Adoption \| Commercial \| Construction
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		103
Impact of ASC 326 Adoption \| Consumer \| Single family residential mortgage
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		(420)
Impact of ASC 326 Adoption \| Consumer \| Other consumer
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses - loans		$ 220