INVESTMENT SECURITIES (Contractual Maturity of AFS Debt Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized Cost
Due within one year	$ 1,028,954
Due after 1 year but within 5 years	656,560
Due after 5 years but within 10 years	424,030
Due after 10 years	9,700,457
Amortized Cost	11,810,001	$ 14,347,346
Fair Value
Due within one year	1,033,024
Due after 1 year but within 5 years	671,008
Due after 5 years but within 10 years	439,653
Due after 10 years	9,904,238
Fair Value	$ 12,047,923	$ 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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