Divestiture-Related Activities - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		6 Months Ended
	Aug. 26, 2012	Jun. 30, 2013	Jul. 01, 2012	Jun. 30, 2013	Jul. 01, 2012	Dec. 31, 2012
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on disposal of an asset held for sale			$ 300,000
Book value of Building sold		311,464,000		311,464,000		297,945,000
Retained liability expenses on divested business		1,000,000	1,200,000	1,800,000	200,000
Proceeds from sale of business	45,200,000
Gain from sale of business	39,000
Building
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Book value of Building sold			$ 0		$ 0