Investment Securities - Schedule of Investment Portfolio (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Securities available for sale, at fair value	$ 39,431	$ 39,508
Securities held to maturity, at carrying value	23,711	22,500
Total investments	$ 63,142	$ 62,008

Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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