Transfers and Servicing of Mortgage Loans (Details) (USD $) In Millions			6 Months Ended
	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2011 Capitalized servicing rights [Member]	Jun. 30, 2010 Capitalized servicing rights [Member]
Activity in the loan servicing portfolio associated with capitalized servicing rights
Balance, beginning of period	$ 173,651	$ 166,075	$ 134,753	$ 127,700
Additions			18,649	12,381
Payoffs, sales and curtailments			(10,966)	(9,984)
Balance, end of period	$ 173,651	$ 166,075	$ 142,436	$ 130,097