EMPLOYEE BENEFIT PLANS - Net Periodic Pension Cost (Details) - Pension plan - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Net periodic pension cost included in the Bank’s consolidated statements of income
Service cost	$ 563	$ 431	$ 1,689	$ 1,050
Interest cost	492	314	1,476	1,281
Expected return on plan assets	(926)	(573)	(2,777)	(2,349)
Amortization of net actuarial loss	270	73	810	508
Net periodic cost	399	245	1,198	490
Other disclosures
Employer contributions	$ 0	$ 0	$ 0	$ 0