Schedule of Amortizable Intangible Asset (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Cost	$ 90,039	$ 90,039
Accumulated Amortization	(31,807)	(20,670)
Net Book Value	58,232	69,369
Customer related intangibles
Finite-Lived Intangible Assets [Line Items]
Cost	44,355	44,355
Accumulated Amortization	(13,142)	(8,214)
Net Book Value	31,213	36,141
Technology
Finite-Lived Intangible Assets [Line Items]
Cost	43,446	43,446
Accumulated Amortization	(16,431)	(10,269)
Net Book Value	27,015	33,177
Other intangibles
Finite-Lived Intangible Assets [Line Items]
Cost	2,238	2,238
Accumulated Amortization	(2,234)	(2,187)
Net Book Value	$ 4	$ 51