Compensation Expense Expected to be Recognized in Respect of Nov-Vested Stock Options Outstanding (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reminder of 2012	$ 251
2013	462
2014	343
2015	109
2016	21
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 1,186

Employee Service Share Based Compensation Unrecognized Compensation Cost Expected To Be Recognized In Year Five

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- Definition

Employee Service Share Based Compensation Unrecognized Compensation Cost Expected To Be Recognized In Year Four

+ References

No definition available.

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- Definition

Employee Service Share Based Compensation Unrecognized Compensation Cost Expected To Be Recognized In Year One

+ References

No definition available.

+ Details

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- Definition

Employee Service Share Based Compensation Unrecognized Compensation Cost Expected To Be Recognized In Year Three

+ References

No definition available.

+ Details

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- Definition

Employee Service, Share Based Compensation, Unrecognized Compensation Costs Expected To Be Recognized For The Remainder Of The Year

+ References

No definition available.

+ Details

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph h

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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