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Auction Rate Securities - ARS Investments (Parenthetical) (Detail) - USD ($) $ in Millions | Mar. 31, 2016 | Jun. 30, 2015
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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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