Debt - Long-Term Debt and Short-Term Borrowings (Parenthetical) (Detail)	Jun. 30, 2016	Dec. 31, 2015
Commercial paper, weighted average interest at 0.750% at June 30, 2016 [Member]
Debt Instrument [Line Items]
Interest rate, weighted average	0.75%
Senior Notes, interest at 6.75%, maturing 2018 [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	6.75%	6.75%
Senior Notes, interest at 7.15%, maturing 2019 [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	7.15%	7.15%
Senior Notes, interest at 3.125%, maturing 2023 [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	3.125%	3.125%
Senior Notes, interest at 3.75%, maturing 2025 [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	3.75%	3.75%
Senior Notes, interest at 4.50%, maturing 2034 [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	4.50%	4.50%
Mortgages and other, interest rates ranging from non-interest bearing to 3.65%, various maturities [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	0.00%	0.00%
Mortgages and other, interest rates ranging from non-interest bearing to 3.65%, various maturities [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate, stated rate	3.65%	3.65%