Stock-Based Compensation - Additional Disclosures (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Stock-based compensation, additional disclosures
Exercises of stock options			$ 4,466
Common stock reserved for future issuance or settlement (in shares)	9,900,000		9,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent			85.00%
Restricted Stock Units
Stock-based compensation, additional disclosures
Weighted average grant-date fair value of RSUs granted	$ 105.71	$ 66.52	$ 114.94	$ 63.24
Total fair value of shares vested from RSU grants	$ 15,100	$ 4,900	$ 25,000	$ 10,200
Total unrecognized compensation cost	35,700		$ 35,700
Total unrecognized compensation cost, period of recognition			2 years 9 months
Excess tax benefits from stock-based compensation	$ 6,300	$ 1,800	$ 9,600	$ 3,400
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			630,528
Stock Options
Stock-based compensation, additional disclosures
Weighted average fair value (in dollars per share)	$ 26.80	$ 16.65	$ 31.54	$ 16.86
Total unrecognized compensation cost	$ 11,300		$ 11,300
Total unrecognized compensation cost, period of recognition			2 years 9 months
Total intrinsic value of options exercised	700	$ 1,300	$ 6,800	$ 2,900
Exercises of stock options	$ 400	$ 1,100	$ 4,500	$ 3,500
Performance Shares [Member]
Stock-based compensation, additional disclosures
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	382,373

Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

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Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Purchase price of common stock expressed as a percentage of its fair value.

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