Fair Value Measurements (Details 3) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired Loans Fair Value Disclosure	$ 101	$ 149
Loans Held-for-sale, Fair Value Disclosure	25	15
Direct Financing Leases and Operating Lease Assets Held for Sale
Goodwill and Other Intangible Assets Fair Value Disclosure
Accrued Income and Other Assets Fair Value Disclosure	46	44
Total assets on a nonrecurring basis at fair value	172	208
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired Loans Fair Value Disclosure
Loans Held-for-sale, Fair Value Disclosure
Direct Financing Leases and Operating Lease Assets Held for Sale
Goodwill and Other Intangible Assets Fair Value Disclosure
Accrued Income and Other Assets Fair Value Disclosure
Total assets on a nonrecurring basis at fair value
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Direct Financing Leases and Operating Lease Assets Held for Sale
Goodwill and Other Intangible Assets Fair Value Disclosure
Accrued Income and Other Assets Fair Value Disclosure	30	19
Total assets on a nonrecurring basis at fair value	30	19
Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Abstract]
Impaired Loans Fair Value Disclosure	101	149
Loans Held-for-sale, Fair Value Disclosure	25	15
Direct Financing Leases and Operating Lease Assets Held for Sale
Goodwill and Other Intangible Assets Fair Value Disclosure
Accrued Income and Other Assets Fair Value Disclosure	16	25
Total assets on a nonrecurring basis at fair value	$ 142	$ 189