SECURITIES, Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Available for Sale, Amortized Cost [Abstract]
Within 1 year	$ 1,615
After 1 year through 5 years	6,864
After 5 years through 10 years	23,918
After 10 years	245,909
Other	461,003
Amortized cost	739,309	$ 775,999
Available for Sale, Fair Value [Abstract]
Within 1 year	1,640
After 1 year through 5 years	7,256
After 5 years through 10 years	25,227
After 10 years	253,697
Other	464,742
Fair value	$ 752,562	$ 803,087

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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