Goodwill by Reporting Unit (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012		Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Goodwill [Line Items]
Goodwill, Beginning					$ 91,489				$ 74,264	$ 91,489	$ 74,264
Goodwill, Accumulated Impairment Loss, Beginning Balance					(69,498)				(69,498)	(69,498)	(69,498)
Goodwill, Net Beginning Balance					21,991				4,766	21,991	4,766
Goodwill, Acquired during the year										1,031	17,044
Effects of Foreign Currency Exchange										31	181
Impairment of goodwill	0	(3,613)	[1]	0	0	0	0	0	0	(3,613)	0	0
Goodwill, Ending	92,551					91,489				92,551	91,489	74,264
Goodwill, Accumulated Impairment Loss, Ending Balance	(73,111)					(69,498)				(73,111)	(69,498)	(69,498)
Goodwill, Net Ending Balance	19,440					21,991				19,440	21,991	4,766
Americas, excluding the USA
Goodwill [Line Items]
Goodwill, Beginning					41,915				24,871	41,915	24,871
Goodwill, Accumulated Impairment Loss, Beginning Balance					(24,871)				(24,871)	(24,871)	(24,871)
Goodwill, Net Beginning Balance					17,044				0	17,044	0
Goodwill, Acquired during the year										1,031	17,044
Effects of Foreign Currency Exchange										0	0
Impairment of goodwill										0	0
Goodwill, Ending	42,946					41,915				42,946	41,915
Goodwill, Accumulated Impairment Loss, Ending Balance	(24,871)					(24,871)				(24,871)	(24,871)
Goodwill, Net Ending Balance	18,075					17,044				18,075	17,044
EMEA
Goodwill [Line Items]
Goodwill, Beginning					25,354				25,354	25,354	25,354
Goodwill, Accumulated Impairment Loss, Beginning Balance					(25,354)				(25,354)	(25,354)	(25,354)
Goodwill, Net Beginning Balance					0				0	0	0
Goodwill, Acquired during the year										0	0
Effects of Foreign Currency Exchange										0	0
Impairment of goodwill										0	0
Goodwill, Ending	25,354					25,354				25,354	25,354
Goodwill, Accumulated Impairment Loss, Ending Balance	(25,354)					(25,354)				(25,354)	(25,354)
Goodwill, Net Ending Balance	0					0				0	0
APAC
Goodwill [Line Items]
Goodwill, Beginning					24,220				24,039	24,220	24,039
Goodwill, Accumulated Impairment Loss, Beginning Balance					(19,273)				(19,273)	(19,273)	(19,273)
Goodwill, Net Beginning Balance					4,947				4,766	4,947	4,766
Goodwill, Acquired during the year										0	0
Effects of Foreign Currency Exchange										31	181
Impairment of goodwill										(3,613)	0
Goodwill, Ending	24,251					24,220				24,251	24,220
Goodwill, Accumulated Impairment Loss, Ending Balance	(22,886)					(19,273)				(22,886)	(19,273)
Goodwill, Net Ending Balance	$ 1,365					$ 4,947				$ 1,365	$ 4,947

[1] The goodwill impairment charge of $3,613 in the third quarter of 2012 was due to a decline in the estimated fair value of the APAC reporting unit attributable to an accelerated decline in the local feature phone business and the recent restructuring of the Company's operations in the region.