Equity Schedule of Stock by Class (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Sep. 08, 2008	Dec. 14, 2007	Nov. 21, 2007	Jun. 04, 2008	May 22, 2008	May 19, 2008
Class of Stock [Line Items]
Senior preferred stock issued, shares	1,000,000	1,000,000
Senior Preferred Stock Value	$ 117,149,000,000	$ 117,149,000,000
Senior preferred stock, shares outstanding	1,000,000	1,000,000
Preferred Stock, Shares Issued	555,374,922	555,374,922
Preferred Stock Issued, Amount	19,130,000,000	19,130,000,000
Preferred stock, shares outstanding	555,374,922	555,374,922
Preferred Stock Outstanding, Amount	19,130,000,000	19,130,000,000
Capital Reserve Amount, current Year, Senior Preferred Stock Purchase Agreement, Amendment	2,400,000,000
Capital reserve amount for the next fiscal year based on the amended Senior Preferred Stock Purchase agreement	1,800,000,000
Annual reduction of capital reserve from 2013 to 2018 based on the Senior Preferred Stock Purchase Agreement, Amendment	600,000,000
Capital reserve amount on January 2018	0
Series 2008-2 Senior Preferred Stock [Member]
Class of Stock [Line Items]
Senior preferred stock issued, shares	1,000,000	1,000,000
Senior Preferred Stock Value	117,149,000,000	117,149,000,000	1,000,000,000.0
Senior preferred stock, shares outstanding	1,000,000	1,000,000
Senior Preferred Stock, Stated Value per Share	$ 117,149		$ 1,000
Series D Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	3,000,000	3,000,000
Preferred Stock Issued, Amount	150,000,000	150,000,000
Preferred stock, shares outstanding	3,000,000	3,000,000
Preferred Stock Outstanding, Amount	150,000,000	150,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	5.25%
Series E Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	3,000,000	3,000,000
Preferred Stock Issued, Amount	150,000,000	150,000,000
Preferred stock, shares outstanding	3,000,000	3,000,000
Preferred Stock Outstanding, Amount	150,000,000	150,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	5.10%
Series F Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	14,000,000	14,000,000
Preferred Stock Issued, Amount	690,000,000	690,000,000
Preferred stock, shares outstanding	14,000,000	14,000,000
Preferred Stock Outstanding, Amount	690,000,000	690,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	0.26%
Preferred Stock, Redemption Terms	P2Y
Series G Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	6,000,000	6,000,000
Preferred Stock Issued, Amount	288,000,000	288,000,000
Preferred stock, shares outstanding	6,000,000	6,000,000
Preferred Stock Outstanding, Amount	288,000,000	288,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	0.40%
Preferred Stock, Redemption Terms	P2Y
Series H Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	8,000,000	8,000,000
Preferred Stock Issued, Amount	400,000,000	400,000,000
Preferred stock, shares outstanding	8,000,000	8,000,000
Preferred Stock Outstanding, Amount	400,000,000	400,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	5.81%
Series I Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	6,000,000	6,000,000
Preferred Stock Issued, Amount	300,000,000	300,000,000
Preferred stock, shares outstanding	6,000,000	6,000,000
Preferred Stock Outstanding, Amount	300,000,000	300,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	5.375%
Series L Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	7,000,000	7,000,000
Preferred Stock Issued, Amount	345,000,000	345,000,000
Preferred stock, shares outstanding	7,000,000	7,000,000
Preferred Stock Outstanding, Amount	345,000,000	345,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	5.125%
Series M Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	9,000,000	9,000,000
Preferred Stock Issued, Amount	460,000,000	460,000,000
Preferred stock, shares outstanding	9,000,000	9,000,000
Preferred Stock Outstanding, Amount	460,000,000	460,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	4.75%
Series N Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	5,000,000	5,000,000
Preferred Stock Issued, Amount	225,000,000	225,000,000
Preferred stock, shares outstanding	5,000,000	5,000,000
Preferred Stock Outstanding, Amount	225,000,000	225,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	5.50%
Series O Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	50,000,000	50,000,000
Preferred Stock Issued, Amount	2,500,000,000	2,500,000,000
Preferred stock, shares outstanding	50,000,000	50,000,000
Preferred Stock Outstanding, Amount	2,500,000,000	2,500,000,000
Preferred Stock, Stated Value per Share	$ 50
Preferred stock, annual dividend rate (as a percent)	7.00%
Convertible Series 2004-1 Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	24,922	24,922
Preferred Stock Issued, Amount	2,492,000,000	2,492,000,000
Preferred stock, shares outstanding	24,922	24,922
Preferred Stock Outstanding, Amount	2,492,000,000	2,492,000,000
Preferred Stock, Stated Value per Share	$ 100,000
Preferred stock, annual dividend rate (as a percent)	5.375%
Series P Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	40,000,000	40,000,000
Preferred Stock Issued, Amount	1,000,000,000	1,000,000,000
Preferred stock, shares outstanding	40,000,000	40,000,000
Preferred Stock Outstanding, Amount	1,000,000,000	1,000,000,000
Preferred Stock, Stated Value per Share	$ 25
Preferred stock, annual dividend rate (as a percent)	4.50%
Series Q Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	15,000,000	15,000,000
Preferred Stock Issued, Amount	375,000,000	375,000,000
Preferred stock, shares outstanding	15,000,000	15,000,000
Preferred Stock Outstanding, Amount	375,000,000	375,000,000
Preferred Stock, Stated Value per Share	$ 25
Preferred stock, annual dividend rate (as a percent)	6.75%
Series R Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	21,000,000	21,000,000		1,200,000	20,000,000
Preferred Stock Issued, Amount	530,000,000	530,000,000		30,000,000	500,000,000
Preferred stock, shares outstanding	21,000,000	21,000,000
Preferred Stock Outstanding, Amount	530,000,000	530,000,000
Preferred Stock, Stated Value per Share	$ 25
Preferred stock, annual dividend rate (as a percent)	7.625%
Series S Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	280,000,000	280,000,000
Preferred Stock Issued, Amount	7,000,000,000	7,000,000,000
Preferred stock, shares outstanding	280,000,000	280,000,000
Preferred Stock Outstanding, Amount	7,000,000,000	7,000,000,000
Preferred Stock, Stated Value per Share	$ 25
Preferred stock, annual dividend rate (as a percent)	7.75%
Preferred Stock, Redemption Terms	P5Y
Series T Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued	89,000,000	89,000,000				1,000,000	8,000,000	80,000,000
Preferred Stock Issued, Amount	2,225,000,000	2,225,000,000				25,000,000	200,000,000	2,000,000,000
Preferred stock, shares outstanding	89,000,000	89,000,000
Preferred Stock Outstanding, Amount	$ 2,225,000,000	$ 2,225,000,000
Preferred Stock, Stated Value per Share	$ 25
Preferred stock, annual dividend rate (as a percent)	8.25%
Maximum [Member] | Series F Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate (as a percent)	11.00%
Maximum [Member] | Series G Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate (as a percent)	11.00%
Minimum [Member] | Series O Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate (as a percent)	7.00%
Minimum [Member] | Series P Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate (as a percent)	4.50%
Minimum [Member] | Series S Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, annual dividend rate (as a percent)	7.75%
Two-year Maturity U.S. Treasury Rate [Member] | Series F Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate, basis spread on variable rate	0.16%
Two-year Maturity U.S. Treasury Rate [Member] | Series G Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate, basis spread on variable rate	0.18%
Ten-year Maturity U.S. Treasury Rate [Member] | Series O Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate, basis spread on variable rate	2.375%
Three-Month LIBOR [Member] | Series P Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate, basis spread on variable rate	0.75%
Three-Month LIBOR [Member] | Series S Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock dividend rate, basis spread on variable rate	4.23%