Changes in Carrying Amount of Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010
Goodwill [Line Items]
Gross Balance prior to the end of year			$ 252,282
Total impairment prior to the end of year			(47,432)
Ending Balance	203,935		204,850
Foreign currency translation adjustments	(1,171)		(915)
Additions-acquisition of ISD	11,380	[1]
Ending Balance	214,144		203,935
Americas
Goodwill [Line Items]
Gross Balance prior to the end of year			187,241
Total impairment prior to the end of year			(47,432)
Ending Balance	139,930		139,809
Foreign currency translation adjustments	(144)		121
Additions-acquisition of ISD	11,380	[1]
Ending Balance	151,166		139,930
EMEA
Goodwill [Line Items]
Gross Balance prior to the end of year			46,846
Ending Balance	44,250		46,846
Foreign currency translation adjustments	(638)		(2,596)
Ending Balance	43,612		44,250
Asia /Pacific
Goodwill [Line Items]
Gross Balance prior to the end of year			18,195
Ending Balance	19,755		18,195
Foreign currency translation adjustments	(389)		1,560
Ending Balance	$ 19,366		$ 19,755

[1] Addition relates to goodwill acquired during the acquisition of ISD. See Note 2, Acquisitions.