Accumulated Other Comprehensive Income (AOCI) - Components of AOCI (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, included in stockholders' equity	$ (22,404)	$ 3,707
Tax effect	4,917	(825)
Net of tax amount	320,772	283,423	$ 258,347	$ 238,392
Net unrealized gain on securities available-for-sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, included in stockholders' equity	(22,366)	3,734
Net unrealized gain on securities available-for-sale securities for which a portion of an other-than-temporary impairment has been recognized in income
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, included in stockholders' equity	(1)	(1)
Unrealized gain from defined benefit pension plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, included in stockholders' equity	(37)	(26)
Accumulated Other Comprehensive Income(Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax amount	$ (17,487)	$ 2,882	$ 4,447	$ 1,247