Retirement Plans - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013 Y	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Age of qualified retirees, minimum	55
Age of qualified retirees, maximum	65
Estimated pension and postretirement medical expense for 2014	$ 20
Estimated amortization of unrecognized net actuarial losses for 2014	28
Net asset value per fund share related to short-term investment funds	$ 1
Budgeted contributions to funded pension plans in 2014	80
Expense related to contribution for several defined contribution plans	41	40	28
Equity securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Current target allocations for plan assets	50.00%
Fixed income securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Current target allocations for plan assets	25.00%
Other investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Current target allocations for plan assets	25.00%
Funded Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for the defined benefit pension plans	1,873	1,937
Unfunded Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation for the defined benefit pension plans	$ 222	$ 216