Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Summary Of Significant Accounting Policies [Line Items]
Stock split ratio			2
Capitalized interest recorded as part of the cost of the assets	$ 0.3	$ 0.7	$ 0.8
Building
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life (in years)	35 years
Machinery and Equipment | Minimum
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life (in years)	3 years
Machinery and Equipment | Maximum
Summary Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life (in years)	18 years