Preferred Stock Preferred Stock Other Disclosures (Details) (USD $)	12 Months Ended		12 Months Ended					12 Months Ended
	Dec. 31, 2012 Floating Rate Non-Cumulative Preferred Stock, Series F ($25 stated value)	Apr. 07, 2010 Floating Rate Non-Cumulative Preferred Stock, Series F ($25 stated value)	Dec. 31, 2012 14,950,000 Depositary Shares each representing a one-fortieth interest in a share of Floating Rate Non-Cumulative Preferred Stock, Series G ($1,000 stated value)	Dec. 31, 2012 14,950,000 Depositary Shares each representing a one-fortieth interest in a share of 6.50% Non-Cumulative Preferred Stock, Series H ($1,000 stated value)	Dec. 31, 2012 6,000,000 Depositary shares each representing a one-fourth interest in a share of Adjustable Rate Cumulative Preferred Stock, Series D ($100 stated value)	Dec. 31, 2012 $2.8575 Cumulative Preferred Stock ($50 stated value)	Oct. 01, 2007 $2.8575 Cumulative Preferred Stock ($50 stated value)	Dec. 31, 2012 Minimum [Member] Floating Rate Non-Cumulative Preferred Stock, Series F ($25 stated value)	Dec. 31, 2012 Minimum [Member] 14,950,000 Depositary Shares each representing a one-fortieth interest in a share of Floating Rate Non-Cumulative Preferred Stock, Series G ($1,000 stated value)	Dec. 31, 2012 Minimum [Member] 6,000,000 Depositary shares each representing a one-fourth interest in a share of Adjustable Rate Cumulative Preferred Stock, Series D ($100 stated value)	Dec. 31, 2012 Maximum [Member] 6,000,000 Depositary shares each representing a one-fourth interest in a share of Adjustable Rate Cumulative Preferred Stock, Series D ($100 stated value)	Dec. 31, 2012 London Interbank Offered Rate (LIBOR) [Member] Floating Rate Non-Cumulative Preferred Stock, Series F ($25 stated value)
Class of Stock [Line Items]
Preferred Stock, Dividened Rate, Basis Spread on Variable Rate			0.75%									0.75%
Preferred Stock, Dividend Rate, Percentage	3.549%		4.056%	6.50%	4.50%	5.715%		3.50%	4.00%	4.50%	10.50%
Preferred Stock, Dividend Rate, Per-Dollar-Amount						$ 2.8575
Preferred Stock, Redemption Price Per Share		$ 25	$ 1,000	$ 1,000	$ 100		$ 50
Preferred Stock, Redemption Price Per Depositary Share					$ 25