SEGMENT REPORTING (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($) segment	Mar. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)
Segment Reporting [Abstract]
Number of operating segments | segment			2
Segment Reporting Information [Line Items]
Net interest income	$ 149,538	$ 135,669	$ 441,748	$ 397,088
Provision (benefit) for credit losses - loans	4,500	2,700	12,500	22,500
Non-interest income	28,774	23,887	86,263	88,460
Non-interest expense	86,819	80,807	257,269	232,650
Income before taxes	86,993	76,049	258,242	230,398
Goodwill	95,674		95,674		$ 71,222
Total Assets	16,080,950		16,080,950		14,265,565
Operating segments | Banking Business
Segment Reporting Information [Line Items]
Net interest income	147,828	135,096	432,328	390,268
Provision (benefit) for credit losses - loans	4,500	2,700	12,500	22,500
Non-interest income	15,741	16,201	46,864	68,708
Non-interest expense	65,076	64,040	190,250	187,733
Income before taxes	93,993	84,557	276,442	248,743
Goodwill	35,721		35,721		35,721
Total Assets	14,768,636		14,768,636		12,745,029
Operating segments | Securities Business
Segment Reporting Information [Line Items]
Net interest income	3,377	3,847	14,059	13,002
Provision (benefit) for credit losses - loans	0	0	0	0
Non-interest income	15,609	8,369	45,169	20,725
Non-interest expense	20,242	13,282	61,169	35,946
Income before taxes	(1,256)	(1,066)	(1,941)	(2,219)
Goodwill	59,953		59,953		35,501
Total Assets	1,246,997		1,246,997		1,450,512
Corporate/Eliminations
Segment Reporting Information [Line Items]
Net interest income	(1,667)	(3,274)	(4,639)	(6,182)
Provision (benefit) for credit losses - loans	0	0	0	0
Non-interest income	(2,576)	(683)	(5,770)	(973)
Non-interest expense	1,501	3,485	5,850	8,971
Income before taxes	(5,744)	$ (7,442)	(16,259)	$ (16,126)
Goodwill	0		0		0
Total Assets	$ 65,317		$ 65,317		$ 70,024