Estimated Amortization Expense on Intangible Assets (Detail) (USD $) In Thousands	6 Months Ended
Jun. 30, 2011
Estimated amortization expense
Remainder of 2011	$ 1,695
2012	3,083
2013	2,865
2014	1,974
2015	0
Total	$ 9,617

The aggregate estimated amortization expense for succeeding fiscal years for intangible assets subject to amortization.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph a(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275

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The amount of amortization expense expected to be recognized during the remainder of the current fiscal year.

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The amount of amortization expense expected to be recognized during year four of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year one of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year three of the five succeeding fiscal years.

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The amount of amortization expense expected to be recognized during year two of the five succeeding fiscal years.

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