Net Deferred Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current deferred income taxes:
Inventories	$ 7,277	$ 5,968
Accrued expenses	78,164	73,171
Derivative instruments	851	(1,474)
Total current	86,292	77,665
Noncurrent net deferred income taxes:
Cost in excess of net assets of business acquired	5,193	2,139
Property and equipment	(21,656)	(21,627)
Compensation payable in common stock	40,329	31,274
Net unrealized gains in other comprehensive income	(1,698)	(1,516)
Net operating loss carryforwards	4,744	4,243
Valuation allowance	(4,523)	(3,912)
Total noncurrent	22,389	10,601
Total	$ 108,681	$ 88,266