EARNINGS PER SHARE - Computation of basic and diluted earnings per share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Numerator:
Net income and comprehensive income	$ 41,137us-gaap_NetIncomeLoss	$ 45,199us-gaap_NetIncomeLoss	$ 125,145us-gaap_NetIncomeLoss	$ 127,519us-gaap_NetIncomeLoss
Denominator:
Weighted-average shares used in computing basic net income per share (in shares)	87,904	87,901	88,115	87,656
Weighted-average shares used in computing diluted net income per share (in shares)	89,400	89,775	89,707	89,667
Net income per share of common stock:
Basic (in usd per share)	$ 0.47us-gaap_EarningsPerShareBasic	$ 0.51us-gaap_EarningsPerShareBasic	$ 1.42us-gaap_EarningsPerShareBasic	$ 1.45us-gaap_EarningsPerShareBasic
Diluted (in usd per share)	$ 0.46us-gaap_EarningsPerShareDiluted	$ 0.50us-gaap_EarningsPerShareDiluted	$ 1.40us-gaap_EarningsPerShareDiluted	$ 1.42us-gaap_EarningsPerShareDiluted
Stock options
Denominator:
Stock options (in shares)	1,367	1,646	1,417	1,754
Restricted stock units
Denominator:
Stock options (in shares)	129	228	175	257

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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