EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Common Share
Net income	$ 56,057	$ 38,821	$ 138,138	$ 114,497
Preferred stock dividends	(77)	(77)	(232)	(232)
Net income attributable to common stockholders	$ 55,980	$ 38,744	$ 137,906	$ 114,265
Average common shares outstanding (in shares)	60,967,892	61,259,419	61,176,715	62,130,598
Total qualifying shares (in shares)	60,967,892	61,259,419	61,176,715	62,130,598
Basic earnings per common share (in dollars per share)	$ 0.92	$ 0.63	$ 2.25	$ 1.84
Diluted Earnings Per Common Share
Dilutive net income attributable to common stockholders	$ 55,980	$ 38,744	$ 137,906	$ 114,265
Average common shares issued and outstanding (in shares)	60,967,892	61,259,419	61,176,715	62,130,598
Total dilutive common shares outstanding (in shares)	61,523,513	61,589,662	61,811,845	62,597,283
Diluted earnings per common share (in dollars per share)	$ 0.91	$ 0.63	$ 2.23	$ 1.83
RSUs
Diluted Earnings Per Common Share
Dilutive effect of average unvested RSUs (in shares)	555,621	330,243	635,130	466,685