Stock Based Compensation - Balance of Outstanding and Exercisable Stock Options (Detail) $ / shares in Units, $ in Millions	6 Months Ended
Dec. 31, 2017 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Option Awards Outstanding, Balance as of June 30, 2017 \| shares	2,490,168
Stock Option Awards Outstanding, Granted \| shares	61,825
Stock Option Awards Outstanding, Exercised \| shares	(85,126)
Stock Option Awards Outstanding, Forfeited \| shares	(79,653)
Stock Option Awards Outstanding, Balance as of December 31, 2017 \| shares	2,387,214
Stock Option Awards Outstanding, Exercisable at December 31, 2017 \| shares	1,943,715
Weighted Average Exercise Price, Balance as of June 30, 2017 \| $ / shares	$ 49.20
Weighted Average Exercise Price, Granted \| $ / shares	45.32
Weighted Average Exercise Price, Exercised \| $ / shares	27.85
Weighted Average Exercise Price, Forfeited \| $ / shares	67.02
Weighted Average Exercise Price, Balance as of December 31, 2017 \| $ / shares	49.26
Weighted Average Exercise Price, Exercisable at December 31, 2017 \| $ / shares	$ 46.64
Aggregate Intrinsic Value, Balance as of December 31, 2017 \| $	$ 14.0
Aggregate Intrinsic Value, Exercisable at December 31, 2017 \| $	$ 14.0

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of share options (or share units) exercised during the current period.

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