Goodwill And Other Intangible Assets (Schedule Of Estimated Amortization Expense) (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011
Goodwill And Other Intangible Assets
2012	$ 9
2013	7
2014	3
2015	3
2016	2
Thereafter	$ 6

Future Amortization Expense After Year Five

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Period Type:	duration

Goodwill And Other Intangible Assets

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Namespace Prefix:	cvg
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The amount of amortization expense expected to be recognized during the fifth twelve-month period following the balance sheet date.