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Auction Rate Securities - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Sep. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Auction Rate Securities with fair value maturing from 2016 to 2018	$ 12.5
Auction Rate Securities with fair value maturing from 2044 to 2046	3.2
Auction Rate Securities with fair value having no stated maturity	2.8
ARS investments, investment grade	4.1
ARS investments, below investment grade	18.5
Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity period one	2016
Maturity period two	2044
Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Maturity period one	2018
Maturity period two	2046
Auction Rate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
ARS investments redeemed at par	$ 1.4

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- Definition

Auction rate securities at investment grade.

+ References

No definition available.

+ Details

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- Definition

Auction rate securities below investment grade.

+ References

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- Definition

Auction rate securities maturing year of specified amount one.

+ References

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- Definition

Auction rate securities maturing year of specified amount two.

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- Definition

Auction rate securities with fair value having no stated maturity.

+ References

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- Definition

Auction rate securities with fair value maturing from stated period.

+ References

No definition available.

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- Definition

Auction rate securities with fair value maturing within specified period.

+ References

No definition available.

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- Definition

The aggregate value of securities held, which were categorized neither as trading nor held-to-maturity, for which the interest rate reset through an auction process, that failed to be liquidated through auction, and which were sold at par value during the period.

+ References

No definition available.

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