Fair Value, Option, Gains and Losses (Details) (USD $) In Millions	6 Months Ended	3 Months Ended		6 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended		6 Months Ended	3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2010 Mortgages held for sale [Member]	Jun. 30, 2011 Mortgages held for sale [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2010 Mortgages held for sale [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Mortgages held for sale [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Mortgages held for sale [Member] Other noninterest income [Member]	Jun. 30, 2011 Mortgages held for sale [Member] Other noninterest income [Member]	Jun. 30, 2010 Loans held for sale [Member]	Jun. 30, 2011 Loans held for sale [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Loans held for sale [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Loans held for sale [Member] Other noninterest income [Member]	Jun. 30, 2010 Loans held for sale [Member] Other noninterest income [Member]	Jun. 30, 2011 Loans held for sale [Member] Other noninterest income [Member]	Jun. 30, 2010 Loans [Member]	Jun. 30, 2011 Loans [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2010 Loans [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Loans [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Loans [Member] Other noninterest income [Member]	Jun. 30, 2011 Loans [Member] Other noninterest income [Member]	Jun. 30, 2010 Long-term debt [Member]	Jun. 30, 2011 Long-term debt [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2010 Long-term debt [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Long-term debt [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Long-term debt [Member] Other noninterest income [Member]	Jun. 30, 2011 Long-term debt [Member] Other noninterest income [Member]	Jun. 30, 2010 Other interests held [Member]	Jun. 30, 2011 Other interests held [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Other interests held [Member] Mortgage banking noninterest income [Member]	Jun. 30, 2011 Other interests held [Member] Other noninterest income [Member]	Jun. 30, 2010 Other interests held [Member] Other noninterest income [Member]	Jun. 30, 2011 Other interests held [Member] Other noninterest income [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Gains on changes in fair value	$ 3,231	$ 1,199	$ 1,769	$ 1,857	$ 0	$ 0	$ 17	$ 0	$ 0	$ 12	$ 3	$ 21	$ 52	$ 3	$ 8	$ 13	$ 0	$ 0	$ (45)	$ (1)	$ (8)	$ (11)	$ 0	$ 0	$ (46)	$ 0	$ 0	$ 14	$ (6)	$ 24