Fair Value Disclosures (Fair Value and Unpaid Principal Balance of LHFS) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
LHFS at fair value	$ 2,488	$ 3,761
Fair Value [Member]
LHFS at fair value	2,488	3,761
Aggregate UPB
LHFS at fair value	2,558	3,652
Fair Value Less Aggregate UPB
LHFS at fair value	$ (70)	$ 109

The aggregate carrying amount of loans receivable that will be sold to other entities. Includes mortgage and all other loans (collectively, loans) not classified as held for investment. Such loans are stated at the lower of cost or market, or elected fair value. Mortgage loans exclude mortgage-backed securities which are considered a debt security (other loan).

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