Short-term Borrowings and Current Portion of Long-term Debt (Narrative) (Details) $ in Millions	Jul. 01, 2016	Jun. 30, 2016	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Short-term Debt [Line Items]
Credit agreement, maximum capacity			$ 2,000	$ 2,250
Line of Credit Facility, Remaining Borrowing Capacity			949
Short-term Debt			1,165	1,181
Performance bonds			151
Current portion of long-term debt			47	401
Revolving credit facility [Member]
Short-term Debt [Line Items]
Short-term Debt			1,035	$ 967
Committed letters of credit [Member]
Short-term Debt [Line Items]
Letters of credit outstanding, amount			16
Domestic and foreign facility [Member]
Short-term Debt [Line Items]
Short term borrowings			130
Uncommitted letters of credit [Member]
Short-term Debt [Line Items]
Letters of credit outstanding, amount			$ 597
Maximum [Member] | Revolving credit facility [Member]
Short-term Debt [Line Items]
Ratio of indebtedness to net capital percent required			0.7
London Interbank Offered Rate (LIBOR) [Member] | Domestic and foreign facility [Member]
Short-term Debt [Line Items]
Interest rate at period end			2.22%
Tranche One [Member] | Bi-Lateral Revolver Debt [Member] | Domestic and foreign facility [Member]
Short-term Debt [Line Items]
Short term borrowings			$ 150
Tranche Two [Member] | Bi-Lateral Revolver Debt [Member] | Domestic and foreign facility [Member]
Short-term Debt [Line Items]
Short term borrowings			$ 30
Subsequent Event [Member] | Maximum [Member] | Revolving credit facility [Member]
Short-term Debt [Line Items]
Ratio of indebtedness to net capital percent required	0.6	0.7
Senior Notes [Member] | Senior Notes, 5.50% due 2016 [Member]
Short-term Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.50%
Current portion of long-term debt			$ 350