SHAREHOLDERS' EQUITY - Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and redemptions		$ 92	$ 97	$ 160	$ 138
Other than temporary impairment losses realized	[1]	0	(28)	(6)	(31)
Total before tax		874	1,238	1,887	2,342
Income tax (expense) or benefit		(301)	(428)	(651)	(800)
Net of tax		$ 573	$ 810	$ 1,236	$ 1,542
The expected U.S. tax rate		35.00%	35.00%	35.00%	35.00%
Reclassification Out Of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net of tax		$ 43	$ (5)	$ 76	$ (4)
Reclassification Out Of Accumulated Other Comprehensive Income | Unrealized gains (losses) on investment securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and redemptions		68	(11)	124	(6)
Other than temporary impairment losses realized		0	0	(6)	(3)
Total before tax		68	(11)	118	(9)
Income tax (expense) or benefit	[2]	(24)	4	(41)	3
Net of tax		44	(7)	77	(6)
Reclassification Out Of Accumulated Other Comprehensive Income | Pension liability adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Acquisition and operating expenses, actuarial gains (losses)	[3]	(5)	(2)	(9)	(6)
Acquisition and operating expenses, prior service (cost) credit	[3]	4	5	8	9
Income tax (expense) or benefit	[2]	0	(1)	0	(1)
Net of tax		$ (1)	$ 2	$ (1)	$ 2

[1] Includes an immaterial amount and $28 for the three-month periods and $6 and $31 for the six-month periods ended June 30, 2015 and 2014, respectively, from change in intent to sell securities

[2] Based on 35% tax rate

[3] These accumulated other comprehensive income components are included in the computation of net periodic pension cost (see Note 10 for additional details).