Earnings per share - Computation of basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net income attributable to common shareholders	$ 471,647	$ 367,253	$ 1,240,362	$ 910,625
Denominator:
Basic - weighted average common shares (in shares)	129,085,563	128,289,720	128,935,696	128,383,549
Increase in weighted average common shares from dilutive effect of equity-based awards (in shares)	2,292,370	1,456,827	1,690,904	1,479,266
Diluted - weighted average common shares, assuming exercise of equity-based awards (in shares)	131,377,933	129,746,547	130,626,600	129,862,815
Basic earnings per share (in USD per share)	$ 3.65	$ 2.86	$ 9.62	$ 7.09
Diluted earnings per share (in USD per share)	$ 3.59	$ 2.83	$ 9.50	$ 7.01