Stock-Based Compensation - Additional Disclosures (Details) - USD ($)		3 Months Ended		6 Months Ended
	Aug. 02, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Stock-based compensation, additional disclosures
Exercises of stock options				$ 2,714,000	$ 4,466,000
Common stock reserved for future issuance or settlement (in shares)		9,500,000		9,500,000
Share-based Payment Arrangement, Expense		$ 7,559,000	$ 6,335,000	$ 16,834,000	$ 15,200,000
Restricted Stock Units
Stock-based compensation, additional disclosures
Weighted average grant-date fair value of RSUs granted		$ 119.76	$ 105.71	$ 133.06	$ 114.94
Total fair value of shares vested from RSU grants		$ 7,400,000	$ 15,100,000	$ 17,900,000	$ 25,000,000.0
Total unrecognized compensation cost		42,300,000		$ 42,300,000
Total unrecognized compensation cost, period of recognition				2 years 9 months 18 days
Excess tax benefits from stock-based compensation		$ 2,700,000	$ 6,300,000	$ 5,900,000	$ 9,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				249,501
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period				70,539
Stock Options
Stock-based compensation, additional disclosures
Weighted average fair value (in dollars per share)		$ 27.85	$ 26.80	$ 33.11	$ 31.54
Total unrecognized compensation cost		$ 13,500,000		$ 13,500,000
Total unrecognized compensation cost, period of recognition				2 years 9 months 18 days
Total intrinsic value of options exercised		1,800,000	$ 700,000	$ 3,000,000.0	$ 6,800,000
Exercises of stock options		$ 1,700,000	$ 400,000	$ 2,700,000	4,500,000
Performance Shares [Member]
Stock-based compensation, additional disclosures
Performance Shares, Performance Target				10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				403,770
Share-based Payment Arrangement, Expense				$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	60,680
2018 Employee Stock Purchase Plan [Member]
Stock-based compensation, additional disclosures
Common stock reserved for future issuance or settlement (in shares)		229,807		229,807
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		85.00%
Share-based Payment Arrangement, Expense		$ 100,000		$ 200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized		250,000		250,000