Earnings (Loss) per Share Level 4 (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Income (Loss) Attributable to Parent [Abstract]
Income (Loss) from Continuing Operations Attributable to Parent																	$ 1,349	$ 1,225	$ 220
Preferred Stock Dividends, Income Statement Impact																	0	10	42
Income loss from Continuing Operations Net of Tax Available to Common Shareholders																	1,349	1,215	178
Dilutive Securities, Effect on Basic Earnings Per Share																	0	10	42
Income (Loss) from Continuing Operations Net of Tax Available to Common Stockholders Diluted																	1,349	1,225	220
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	37		0		(617)		29		(70)		(72)		(423)		(484)		(551)	(1,049)	(258)
Net Income (Loss) Attributable to Parent	382		388		(467)		495		314		293		(190)		(241)		798	176	(38)
Net Income (Loss) Available to Common Stockholders, Basic	382		388		(467)		495		314		293		(190)		(251)		798	166	(80)
Net Income (Loss) Available to Common Stockholders, Diluted																	$ 798	$ 176	$ (38)
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Weighted Average Number of Shares Outstanding, Basic	429.6		437.2		450.6		449.8		451.1		452.1		451.4		436.3		441.8	447.7	437.7
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements																	6.3	4.5	2.2
Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock															21.2		0	6.2	0
Incremental Common Shares Attributable to Dilutive Effect of Call Options and Warrants																	12.1	32.2	26.0
Weighted Average Number of Shares Outstanding, Diluted	442.6	[1]	450.8	[1]	467.9	[1]	478.6	[1]	486.1	[1]	490.6	[1]	489.0	[1]	493.1	[1]	460.2	490.6	465.9
Earnings Per Share, Basic and Diluted [Abstract]
Income (Loss) from Continuing Operations, Per Basic Share																	$ 3.05	$ 2.71	$ 0.41
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share																	$ (1.24)	$ (2.34)	$ (0.59)
Earnings Per Share, Basic	$ 890,000.00		$ 890,000.00		$ (1,040,000.00)		$ 1,100,000.00		$ 700,000.00		$ 650,000.00		$ (420,000.00)		$ (580,000.00)		$ 1.81	$ 0.37	$ (0.18)
Income (Loss) from Continuing Operations, Per Diluted Share																	$ 2.93	$ 2.50	$ 0.38
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share																	$ (1.20)	$ (2.14)	$ (0.55)
Earnings Per Share, Diluted	$ 860,000.00		$ 860,000.00		$ (1,000,000.00)		$ 1,030,000.00		$ 650,000.00		$ 600,000.00		$ (390,000.00)		$ (490,000.00)		$ 1.73	$ 0.36	$ (0.17)
Weighted Average Number Diluted Shares Outstanding Assuming Conversion of Preferred Shares																			486.8
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount																			20.9

[1] [1]Weighted average common shares outstanding and dilutive potential common shares are used in the calculation of diluted earnings (losses) per common share in periods of losses when the impact is dilutive to income from continuing operations, net of tax, available to common shareholders.