Net Income Per Share - Stock Options Excluded from the Computation of Dilutive Weighted Average Shares Outstanding (Details)	3 Months Ended
	Sep. 30, 2018 $ / shares shares
Stock Options
Employee equity awards were excluded from the calculation of dilutive weighted average shares outstanding because their effect would be anti-dilutive
Options to purchase shares of common stock (in shares) | shares	262,343
Stock Options
Employee equity awards were excluded from the calculation of dilutive weighted average shares outstanding because their effect would be anti-dilutive
Exercise price range, low end of range (in dollars per share)	$ 115.36
Exercise price range, high end of range (in dollars per share)	$ 116.00