Stock Incentive Plans - Summary of the status and shares subject to restricted stock units and average price per share (Details) - Restricted Stock Units (RSUs)	12 Months Ended
	Jun. 30, 2020 $ / shares shares
Number of Shares
Beginning balance, nonvested (in shares) | shares	374,080
Granted (in shares) | shares	150,489
Vested (in shares) | shares	(158,823)
Canceled (in shares) | shares	(15,173)
Ending balance, nonvested (in shares) | shares	350,573
Weighted-Average Grant Date Fair Value
Beginning balance, nonvested (in USD per share) | $ / shares	$ 155.07
Granted (in USD per share) | $ / shares	160.54
Vested (in USD per share) | $ / shares	147.20
Canceled (in USD per share) | $ / shares	162.41
Ending balance, nonvested (in USD per share) | $ / shares	$ 160.66
Director
Number of Shares
Beginning balance, nonvested (in shares) | shares	8,003
Granted (in shares) | shares	8,300
Vested (in shares) | shares	(8,041)
Ending balance, nonvested (in shares) | shares	8,262
Weighted-Average Grant Date Fair Value
Beginning balance, nonvested (in USD per share) | $ / shares	$ 147.38
Granted (in USD per share) | $ / shares	187.31
Vested (in USD per share) | $ / shares	147.38
Canceled (in USD per share) | $ / shares	$ 187.49