Selected Segment Financial Data, Revenues and Operating Income (Loss) (Detail) (USD $) In Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Segment Reporting Information [Line Items]
Revenues	$ 113,366	$ 92,423	$ 217,909	$ 180,166
Operating income	10,422	4,366	17,920	3,461
Americas
Segment Reporting Information [Line Items]
Revenues	57,974	50,185	110,304	96,501
Operating income	9,678	6,829	15,641	9,888
EMEA
Segment Reporting Information [Line Items]
Revenues	41,880	30,466	84,021	62,379
Operating income	4,136	358	10,396	217
Asia /Pacific
Segment Reporting Information [Line Items]
Revenues	13,512	11,772	23,584	21,286
Operating income	$ (3,392)	$ (2,821)	$ (8,117)	$ (6,644)