INVESTMENT SECURITIES (Contractual Maturity of AFS Debt Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortized Cost
Due within one year	$ 349,080
Due after 1 year but within 5 years	115,239
Due after 5 years but within 10 years	353,072
Due after 10 years	10,069,919
Amortized Cost	10,887,310	$ 14,347,346
Fair Value
Due within one year	349,831
Due after 1 year but within 5 years	119,460
Due after 5 years but within 10 years	368,100
Due after 10 years	10,241,581
Fair Value	$ 11,078,972	$ 14,339,758

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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