Net Loss Per Share - Additional Information (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	3 Months Ended
Sep. 30, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Principal amount of convertible subordinated notes	$ 215.0
Dilutive convertible notes outstanding	0

Dilutive Securities Convertible Notes and Securities Shares

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration