DEBT - Term Debt of Outstanding (Detail) - Senior Notes - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt	$ 3,792,000,000	$ 3,794,000,000
$500 million, 7.20% due June 15, 2018
Debt Instrument [Line Items]
Long-term debt	501,000,000	502,000,000
Senior notes	$ 500,000,000
Debt instrument, stated interest rate	7.20%
$300 million, 6.30% due August 1, 2018
Debt Instrument [Line Items]
Long-term debt	$ 304,000,000	307,000,000
Senior notes	$ 300,000,000
Debt instrument, stated interest rate	6.30%
$400 million, 2.625% due October 1, 2019
Debt Instrument [Line Items]
Long-term debt	$ 398,000,000	398,000,000
Senior notes	$ 400,000,000
Debt instrument, stated interest rate	2.65%
$600 million, 3.15% due December 1, 2022
Debt Instrument [Line Items]
Long-term debt	$ 595,000,000	595,000,000
Senior notes	$ 600,000,000
Debt instrument, stated interest rate	3.15%
$600 million, 3.85% due October 1, 2024
Debt Instrument [Line Items]
Long-term debt	$ 595,000,000	595,000,000
Senior notes	$ 600,000,000
Debt instrument, stated interest rate	3.85%
$250 million, 8.15% due June 15, 2038
Debt Instrument [Line Items]
Long-term debt	$ 264,000,000	263,000,000
Senior notes	$ 250,000,000
Debt instrument, stated interest rate	8.15%
$400 million, 4.625% due December 1, 2042
Debt Instrument [Line Items]
Long-term debt	$ 396,000,000	396,000,000
Senior notes	$ 400,000,000
Debt instrument, stated interest rate	4.625%
$750 million, 4.95% due October 1, 2044
Debt Instrument [Line Items]
Long-term debt	$ 739,000,000	$ 738,000,000
Senior notes	$ 750,000,000
Debt instrument, stated interest rate	4.95%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: 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 2: 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 3: 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

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Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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

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