Schedule of Revenue and Income for Discontinued Operations (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Revenue
Loss before income taxes				(37,568)
Provision for income taxes				13,679
Net loss attributable to discontinued operations				$ (23,889)
Basic				$ (0.18)
Diluted				$ (0.17)
Basic	136,351	132,556	135,998	132,877
Diluted	141,112	138,192	135,998	138,747

Pretax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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