Securities - Remaining Maturity of Securities Available for Sale (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Available for Sale - Amortized Cost
Due in One Year or Less	$ 9,206.2	$ 6,249.5
Due After One Year Through Five Years	21,012.7	20,017.2
Due After Five Years Through Ten Years	5,774.1	6,545.3
Due After Ten Years	1,048.8	1,052.8
AMORTIZED COST	37,041.8	33,864.8
Available for Sale - Fair Value
Due in One Year or Less	9,162.8	6,227.0
Due After One Year Through Five Years	20,943.9	19,937.8
Due After Five Years Through Ten Years	5,740.8	6,535.1
Due After Ten Years	1,041.3	1,042.2
Total	$ 36,888.8	$ 33,742.1

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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