Investment Securities - Schedule of Contractual Maturities of Securities Held to Maturity (Detail) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Carrying Value
Due after 1 year through 5 years	$ 199
Due after 5 years through 10 years	1,251
Due after 10 years	23,630
Carrying Value	25,080	$ 24,619
Fair Value
Due after 1 year through 5 years	200
Due after 5 years through 10 years	1,355
Due after 10 years	24,899
Fair Value	$ 26,454	$ 25,317

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

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-Name Accounting Standards Codification
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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the fifth through tenth fiscal year following the latest fiscal year.

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Fair value of held-to-maturity debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of held-to-maturity debt securities maturing after the tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Fair value of held-to-maturity debt securities maturing in the sixth through tenth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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