Casualty, Environmental and Other Reserves (Loss Contingencies Accrual) (Details) (USD $) In Millions, unless otherwise specified	Dec. 27, 2013	Dec. 28, 2012	Dec. 30, 2011	Dec. 31, 2010
Casualty [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	$ 72	$ 88
Loss Contingency, Accrual, Noncurrent	208	237
Loss Contingency Accrual	280	325	372	375
Personal Injury [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	59	75
Loss Contingency, Accrual, Noncurrent	148	158
Loss Contingency Accrual	207	233
Occupational [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	3	5
Loss Contingency, Accrual, Noncurrent	20	31
Loss Contingency Accrual	23	36
Asbestos [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	10	8
Loss Contingency, Accrual, Noncurrent	40	48
Loss Contingency Accrual	50	56
Environmental [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	59	33
Loss Contingency, Accrual, Noncurrent	41	55
Loss Contingency Accrual	100	88	83	107
Other [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	20	19
Loss Contingency, Accrual, Noncurrent	51	45
Loss Contingency Accrual	71	64	64	59
Casualty, Environmental and Other [Member]
Contingencies [Line Items]
Loss Contingency, Accrual, Current	151	140
Loss Contingency, Accrual, Noncurrent	300	337
Loss Contingency Accrual	$ 451	$ 477	$ 519	$ 541