NOTES PAYABLE - Summary of Notes Payable (Details) - USD ($) $ in Millions		Jun. 30, 2015		Dec. 31, 2014
Debt Instrument [Line Items]
Notes payable		$ 5,425		$ 5,282
3.45% senior notes due August 2015
Debt Instrument [Line Items]
Notes payable		300		300
2.65% senior notes due February 2017
Debt Instrument [Line Items]
Notes payable	[1]	653		653
8.50% senior notes due May 2019
Debt Instrument [Line Items]
Notes payable		0		850
2.40% senior notes due March 2020
Debt Instrument [Line Items]
Notes payable		550		0
4.00% senior notes due February 2022
Debt Instrument [Line Items]
Notes payable	[2]	350		350
3.625% senior notes due June 2023
Debt Instrument [Line Items]
Notes payable		700		700
3.625% senior notes due November 2024
Debt Instrument [Line Items]
Notes payable	[2]	749		749
3.25% senior notes due March 2025
Debt Instrument [Line Items]
Notes payable		448	[2]	0
6.90% senior notes due December 2039
Debt Instrument [Line Items]
Notes payable	[2]	397		397
6.45% senior notes due August 2040
Debt Instrument [Line Items]
Notes payable	[2]	448		448
5.50% subordinated notes due September 2052
Debt Instrument [Line Items]
Notes payable		500		500
2.26% yen-denominated Uridashi notes due September 2016
Debt Instrument [Line Items]
Notes payable		65		66
1.84% yen-denominated Samurai notes due July 2016
Debt Instrument [Line Items]
Notes payable		129		131
3.60% yen-denominated loan due July 2015
Debt Instrument [Line Items]
Notes payable		82	[3]	83
3.00% yen-denominated loan due August 2015
Debt Instrument [Line Items]
Notes payable		41		41
Capitalized Lease Obligations
Debt Instrument [Line Items]
Notes payable		$ 13		$ 14

[1] Principal amount plus an issuance premium that is being amortized over the life of the notes

[2] Principal amount net of an issuance discount that is being amortized over the life of the notes

[3] Paid off on July 24, 2015 at its specific maturity date