LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES - LOANS - Amortized Cost Basis of Collateral Dependent Impaired Loans (Details) $ in Thousands	Jun. 30, 2022 USD ($)
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	$ 6,658
Real Estate
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	2,037
Equipment
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	4,621
REAL ESTATE LOANS
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	950
REAL ESTATE LOANS | Home equity.
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	151
REAL ESTATE LOANS | One-to-four-family
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	799
REAL ESTATE LOANS | Real Estate
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	950
REAL ESTATE LOANS | Real Estate | Home equity.
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	151
REAL ESTATE LOANS | Real Estate | One-to-four-family
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	799
CONSUMER LOANS
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	649
CONSUMER LOANS | Indirect home improvement
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	558
CONSUMER LOANS | Marine
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	91
CONSUMER LOANS | Equipment
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	649
CONSUMER LOANS | Equipment | Indirect home improvement
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	558
CONSUMER LOANS | Equipment | Marine
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	91
COMMERCIAL BUSINESS LOANS | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	5,059
COMMERCIAL BUSINESS LOANS | Real Estate | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	1,087
COMMERCIAL BUSINESS LOANS | Equipment | Commercial and industrial
Financing Receivable, Recorded Investment [Line Items]
Amortized cost basis of collateral dependent impaired loans	$ 3,972