Intangbile assets (Details) (USD $)	12 Months Ended
	Dec. 31, 2011	Jan. 01, 2011	Jan. 02, 2010
Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense	$ 28,000,000	$ 5,600,000	$ 3,800,000
Indefinite Lived Intangible Assets	92,002,000	92,002,000
Finite Lived Intangible Assets	353,276,000	355,641,000
Accumulated Amortization	(82,364,000)	(56,689,000)
Total Intangible assets, less accumulated amortization	362,914,000	390,954,000
Future Amortization Expense, Year One	27,900,000
Future Amortization Expense, Year Two	27,800,000
Future Amortization Expense, Year Three	27,800,000
Future Amortization Expense, Year Four	27,100,000
Future Amortization Expense, Year Five	21,800,000
Trade Names [Member]
Intangible Assets [Line Items]
Indefinite Lived Intangible Assets	92,002,000	92,002,000
Routes And Noncompete Agreements [Member]
Intangible Assets [Line Items]
Finite-lived Intangible Assets, Period Increase (Decrease)	2,400,000
Routes [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets	95,567,000	96,938,000
Accumulated Amortization	(55,333,000)	(48,361,000)
Permits [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets	251,413,000	251,413,000
Accumulated Amortization	(24,386,000)	(5,563,000)
Non-compete agreements [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets	5,018,000	6,012,000
Accumulated Amortization	(2,162,000)	(2,417,000)
Trade Names [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets	539,000	539,000
Accumulated Amortization	(37,000)	(2,000)
Royalty, consulting and leasehold [Member]
Intangible Assets [Line Items]
Finite Lived Intangible Assets	739,000	739,000
Accumulated Amortization	$ (446,000)	$ (346,000)