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Auction Rate Securities - ARS Investments (Parenthetical) (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Jun. 30, 2015
Investments Debt And Equity Securities [Abstract]
Investment securities accretion	$ 4.1	$ 2.7

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- Definition

Accumulated accretion on investment securities.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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