Commitments and Contingencies - Self-Insured Health and Workers' Compensation Plans (Details) (USD $)	12 Months Ended
	Dec. 28, 2014 claim	Dec. 29, 2013 claim	Dec. 30, 2012 claim
Self-insured health plan
Loss Contingencies [Line Items]
Accrual for self-insurance programs	$ 100,000	$ 200,000
Number of claims that exceeded annual coverage limits	0	0	0
Self-insured health plan | Minimum
Loss Contingencies [Line Items]
Annual coverage limit	50,000
Self-insured health plan | Maximum
Loss Contingencies [Line Items]
Annual coverage limit	85,000
Self-insured workers' compensation plan
Loss Contingencies [Line Items]
Accrual for self-insurance programs	300,000	200,000
Number of claims that exceeded annual coverage limits	0	0	0
Self-insured workers' compensation plan | Minimum
Loss Contingencies [Line Items]
Annual coverage limit	250,000
Self-insured workers' compensation plan | Maximum
Loss Contingencies [Line Items]
Annual coverage limit	$ 350,000