The Reconciliation of the U.S. Federal Statutory Tax Rate to the Effective Rate (Detail)	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Reconciliation of Statutory Federal Tax Rate [Line Items]
Statutory U.S. federal income tax rate	35.00%	35.00%	35.00%
State income taxes, net of federal benefit	0.30%	0.90%	1.00%
Federal benefit of R&D and foreign tax credits	(8.60%)	(6.90%)	(11.30%)
Tax effect of international operations	(7.90%)	(3.70%)	0.70%
Net effect of tax audit activity	2.10%	1.00%	(1.30%)
Tax effect of enacted statutory rate changes	0.20%	0.00%	0.00%
Federal tax on unremitted earnings of certain foreign subsidiaries	0.10%	0.20%	0.10%
Valuation allowance adjustments	(18.10%)	(1.00%)	0.00%
Other	1.20%	(0.50%)	0.30%
Effective income tax rate on operations	4.30%	25.00%	24.50%

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

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The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in the valuation allowance for deferred tax assets.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement and the expected income tax expense or benefit that is attributable to changes in the income tax laws or rates.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to all other items not otherwise listed in the existing taxonomy.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state and local income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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Effective Income Tax Rate International Operations

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Effective Income Tax Rate Reconciliation Audit Activity

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Effective Income Tax Rate Reconciliation, Federal Tax on Unremitted Earnings of Certain Foreign Subsidiaries

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Effective Income Tax Rate Reduction, Research and Development and Foreign Tax Credits

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