Changes in Operations Future Minimum Lease Payments (Details) - Freightliner [Member] $ in Thousands	Mar. 25, 2015 USD ($)
Capital lease minimum payments due April-December 2015	$ 14,322
Capital lease minimum payments due 2016	16,992
Capital lease minimum payments due 2017	10,509
Capital lease minimum payments due 2018	7,050
Capital lease minimum payments due 2019	6,545
Capital lease minimum payments due thereafter	37,755
Capital lease total minimum payments	93,173
Operating lease minimum payments due April-December 2015	64,600
Operating lease minimum payments due 2016	74,622
Operating lease minimum payments, due 2017	64,465
Operating lease minimum payments due 2018	56,425
Operating lease minimum payments due 2019	43,492
Operating lease minimum payments due thereafter	139,157
Operating lease total minimum payments	442,761
Total lease payments due April-December 2015	78,922
Total lease payments due 2016	91,614
Total lease payments due 2017	74,974
Total lease payments due 2018	63,475
Total lease payments due 2019	50,037
Total lease minimum payments due thereafter	176,912
Total lease minimum payments	$ 535,934