Commitments and contingent matters (Details) In Millions	9 Months Ended	12 Months Ended
Sep. 30, 2011 USD ($)	Dec. 31, 2010 EUR (€)
Commitments and Contingencies Disclosure [Abstract]
Operating leases residual value guarantee	$ 30.1
Amount of claim		20
Settlement amount	$ 10

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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