Components of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Inventory [Line Items]
Raw materials and supplies	$ 150,505	$ 166,359
Work-in-process and finished goods	349,777	314,438
LIFO reserve	(48,109)	(50,709)
Total inventories	$ 452,173	$ 430,088