Net Purchase Price Allocation to Assets and Liabilities based on their Estimated Fair Value (Detail) (2011 Acquisitions of Assets and Businesses, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
2011 Acquisitions of Assets and Businesses
Business Acquisition [Line Items]
Property, plant & equipment	$ 35,000
Other assets/deposits	11,000
Debt	(17,000)
Cash paid in 2011 for acquisitions and deposits	$ 29,000