The amount of cash contributed to the Pioneer Bank Charitable Foundation.

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The number of shares of common stock contributed to the Pioneer Bank Charitable Foundation.

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The face amount of loans that will be sold to other entities.

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The cash inflow from the additional capital contribution to the entity.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Mutual Holding Company Reorganization and Minority Stock Issuance (Details) - USD ($)		12 Months Ended
	Jul. 17, 2019	Jun. 30, 2020	Jun. 30, 2019
Mutual Holding Company Reorganization and Minority Stock Issuance
Net proceeds from sale of stock		$ 109,055,000
Stock contributed to Pioneer Bank Charitable Foundation (in shares)	519,554
Cash contributed to Pioneer Bank Charitable Foundation	$ 250,000
Loans held for sale		$ 0	$ 0
Pioneer Bancorp, MHC
Mutual Holding Company Reorganization and Minority Stock Issuance
Sale of stock (in shares)	14,287,723
Ownership Interest In Reporting Entity Percentage		55.00%
Pioneer Bank ESOP
Mutual Holding Company Reorganization and Minority Stock Issuance
Numbers of shares owned by ESOP		1,018,325
Initial Public Offering
Mutual Holding Company Reorganization and Minority Stock Issuance
Sale of stock (in shares)	11,170,402
Share price	$ 10.00
Net proceeds from sale of stock	$ 109,100,000