DEBT (Long-Term Debt) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total long-term debt	$ 3,898	$ 3,651
Debt issuance costs	(23)	(25)
Less: Current portion of long-term debt	158	159
Total long-term debt, net of current portion	3,740	3,492
3.20% Senior Notes Due 2016 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 150	150
Debt instrument, interest rate	3.20%
Debt instrument, maturity date	Apr. 01, 2016
2.70% Senior Notes due April 2019 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 300	300
Debt instrument, interest rate	2.70%
Debt instrument, maturity date	Apr. 01, 2019
4.75% Senior Notes due January 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 526	522
Debt instrument, interest rate	4.75%
Debt instrument, maturity date	Jan. 30, 2020
2.50% Senior Notes due March 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 299	299
Debt instrument, interest rate	2.50%
Debt instrument, maturity date	Mar. 30, 2020
4.70% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 566	554
Debt instrument, interest rate	4.70%
Debt instrument, maturity date	Apr. 01, 2021
4.25% Senior Notes due April 2024 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 324	313
Debt instrument, interest rate	4.25%
Debt instrument, maturity date	Apr. 01, 2024
3.50% Senior Notes due March 2025 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 609	601
Debt instrument, interest rate	3.50%
Debt instrument, maturity date	Mar. 30, 2025
6.95% Senior Notes Due 2037 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 174	247
Debt instrument, interest rate	6.95%
Debt instrument, maturity date	Jul. 01, 2037
5.75% Senior Notes Due 2040 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 244	368
Debt instrument, interest rate	5.75%
Debt instrument, maturity date	Jan. 30, 2040
4.70% Senior Notes due March 2045 [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 300	300
Debt instrument, interest rate	4.70%
Debt instrument, maturity date	Mar. 30, 2045
Other [Member]
Debt Instrument [Line Items]
Other	$ 19	22
Secured Receivables Credit Facility [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 410	$ 0
Debt instrument, interest rate	1.20%

Contractual interest rate for funds borrowed, under the debt agreement.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 210
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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