FAIR VALUE OF FINANCIAL INSTRUMENTS (New Notes) (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Feb. 26, 2013
Debt Instrument [Line Items]
Issuance date	Feb. 26, 2013
Debt to capitalization, covenant ratio	60.00%
2013 Senior Notes [Member]
Debt Instrument [Line Items]
Face amount		$ 400
3.70% Senior notes due 2023 [Member]
Debt Instrument [Line Items]
Face amount		225
Interest rate	3.70%	3.70%
Maturity date	Feb. 26, 2023
3.85% Senior notes due 2025 [Member]
Debt Instrument [Line Items]
Face amount		100
Interest rate	3.85%	3.85%
Maturity date	Feb. 26, 2025
4.05% Senior notes due 2028 [Member]
Debt Instrument [Line Items]
Face amount		75
Interest rate	4.05%	4.05%
Maturity date	Feb. 26, 2028
4.11% Senior Notes [Member]
Debt Instrument [Line Items]
Maturity date	Sep. 26, 2028
Debt Instrument, Issuable Face Amount		$ 100
Debt Instrument, Interest Rate, Issuable Stated Percentage		4.11%