Other Intangible Assets, Changes in Net Carrying Amount (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Gross amount
Other intangible assets, beginning	$ 34,256	$ 3,147
Intangible assets acquired during the period	20,369	31,106
Foreign currency translation effect on balances	282	3
Other intangible assets, ending	54,907	34,256
Accumulated amortization
Other intangible assets, beginning	(1,206)	(188)
Other intangible assets acquired during the period
Amortization expense	(2,787)	(1,018)
Foreign currency translation effect on balances	(22)
Other intangible assets, ending	$ (4,015)	$ (1,206)