INVESTMENT SECURITIES - Contractual Maturities, Available for Sale (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Amortized Cost
Due within one year	$ 711
Due after one year through five years	3,152
Due after five years through ten years	2,038
Due after ten years	779
Mortgage and asset-backed securities	3,689
Amortized Cost	10,369	$ 12,104
Fair Value
Due within one year	709
Due after one year through five years	3,092
Due after five years through ten years	1,962
Due after ten years	758
Mortgage and asset-backed securities	3,579
Fair Value	$ 10,100	$ 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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