SECURITIES, Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Available for Sale, Amortized Cost [Abstract]
Within 1 year	$ 6,731
After 1 year through 5 years	3,398
After 5 years through 10 years	26,079
After 10 years	241,565
Other	498,226
Amortized cost	775,999	$ 706,437
Available for Sale, Fair Value [Abstract]
Within 1 year	6,761
After 1 year through 5 years	3,585
After 5 years through 10 years	26,959
After 10 years	252,133
Other	513,649
Fair value	$ 803,087	$ 707,650

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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