Post-Retirement Plans - Additional Information (Detail) (USD $)	9 Months Ended
	Oct. 06, 2012	Oct. 08, 2011
Pension and Other Postretirement Benefits Disclosure [Line Items]
Cash contributions to qualified pension plans	$ 18,143,000	$ 10,962,000
Total cost and employer contributions	15,600,000	14,200,000
Date of acquisition	May 20, 2011
Lepage Bakeries Inc
Pension and Other Postretirement Benefits Disclosure [Line Items]
Employer contributions to 401(k) Plan	$ 100,000