NET INCOME PER COMMON SHARE - Schedule of Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2020
Numerator:
Net income	$ 49,970	$ 51,687
Adjustment for Basic EPS:
Earnings allocated to unvested shareholders	(325)	(358)
Adjusted net income	$ 49,645	$ 51,329
Denominator:
Weighted average common shares outstanding – Basic	47,369,764	47,267,921	47,267,921
Effect of dilutive shares:
Common stock equivalents arising from stock options and ESPP	191	165
Restricted stock awards and units and performance units	70,326	61,618
Weighted average common shares outstanding – Diluted	47,440,281	47,329,704	47,329,704
Basic	$ 1.05	$ 1.09
Diluted	$ 1.05	$ 1.08