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Auction Rate Securities - Additional Information (Detail) $ in Millions	6 Months Ended
	Dec. 31, 2015 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Auction rate securities with fair value having no stated maturity	$ 1.8
Maturity period one	2018
Auction Rate Securities Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
ARS investments redeemed at par value	$ 0.6
Auction Rate Securities with fair value maturing from 2016 to 2018	$ 12.4

X

- Definition

Auction rate securities maturing year of specified amount one.

+ References

No definition available.

+ Details

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- Definition

Auction rate securities with fair value having no stated maturity.

+ References

No definition available.

+ Details

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X

- Definition

Amount of available-for-sale debt securities at fair value that do not have a single maturity date and which the entity has decided to disclose separately rather than allocating the fair value over several maturity groupings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

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X

- 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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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