Marketable Investment Securities - Schedule of Maturities of Debt Securities Classified as Cash Equivalents and Available-For-Sale (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Jun. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	$ 229,467	$ 270,224
Due within one year, Amortized cost	105,370
Due after one year through five years, Amortized cost	42,250
Due after five years, Amortized cost
Total	229,467
Estimated fair value	229,553us-gaap_AvailableForSaleSecurities	270,586us-gaap_AvailableForSaleSecurities
Due within one year, Estimated fair value	105,406
Due after one year through five years, Estimated fair value	42,300
Due after five years, Estimated fair value
Total	229,553
Cash
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	57,010	45,181
Estimated fair value	57,010	45,181
Cash Equivalents
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	2,699	19,639
Estimated fair value	2,699	19,640
Restricted Cash
Schedule of Available-for-sale Securities [Line Items]
Amortized cost	22,138
Estimated fair value	$ 22,138

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the sixth fiscal year through the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of investment in available-for-sale debt securities with a single maturity date.

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