Employee Benefits (Detail) - Components of Net Periodic Pension Expense (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Service cost	$ 1,775		$ 1,890		$ 1,875
Interest cost	980		1,010		840
Expected return on plan assets	(115)		(125)
Recognition of actuarial gain	(215)		(135)		(350)
Recognition of termination benefits	175		65		65
Total defined benefit pension expense (1)	$ 2,600	[1]	$ 2,705	[1]	$ 2,430	[1]

[1] Pension expense is classified in SG&A in the Consolidated Statements of Operations.