Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Income Taxes (Textual) [Abstract]
Effective income tax rate	32.20%	27.70%	29.90%	32.20%
U.S. federal statutory rate	35.00%	35.00%
Settlement With IRS			3.00%
Reduction in effective Tax rate due to tax benefit related to the favorable resolution of U.S. federal tax legislation uncertainties existing at the acquisition date of CTG	0.00%	4.00%	0.00%	0.00%
Reduction in effective tax rate as compared to U.S. federal statutory rate due to foreign jurisdictions taxes	2.00%	3.00%
Reduction in effective tax rate as compared to U.S. federal statutory rate due to foreign and domestic tax credits	4.00%	5.00%		3.00%
Increase in effective tax rate due to adjustments to reserves for tax contingencies, included interest	2.00%	2.00%
Increased effective tax rate due to state income taxes	1.00%	1.00%
Unrecognized Tax Benefits	$ 151.0		$ 151.0		$ 147.1
Total unrecognized benefits, if recognized would Impact effective tax rate	203.7		203.7		203.9
Increase in effective tax due to repatriation of non U.S Earnings		1.00%
Increase in effective tax rate due to enactment of health care reform legislation				2.00%
Enactment of health care reform legislation charge				$ 10

Income Taxes Textual Abstract.

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Increase in tax liabilities due to the enactment of health care reform legislation percentage.

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Increase in tax liability due to enactment of health care reform legislation amount.

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Settlement With IRS.

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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.

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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 that can be explained by the difference between statutory income tax rates in foreign jurisdictions and the domestic federal statutory income tax rate recorded during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to the repatriation of foreign earnings under enacted tax laws.

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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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The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate attributable to changes in all income tax contingencies, whether recorded or adjusted, during the period.

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The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate that can be explained by all tax credits generated or utilized under enacted tax laws during the period.

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The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable to foreign income tax settlements during the period.

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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-Glossary Unrecognized Tax Benefit

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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