INVESTMENT SECURITIES - Contractual Maturities, Available for Sale (Detail) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Amortized Cost
Due within one year	$ 722
Due after one year through five years	3,016
Due after five years through ten years	2,100
Due after ten years	784
Mortgage and asset-backed securities	3,451
Amortized Cost	10,073	$ 12,104
Fair Value
Due within one year	720
Due after one year through five years	2,964
Due after five years through ten years	2,022
Due after ten years	772
Mortgage and asset-backed securities	3,365
Fair Value	$ 9,843	$ 12,302

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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