SECURITIES, Amortized Cost and Fair Value of Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Available for Sale, Amortized Cost [Abstract]
Within 1 year	$ 377
After 1 year through 5 years	4,595
After 5 years through 10 years	26,284
After 10 years	243,845
Other	493,511
Amortized cost	768,612	$ 775,999
Available for Sale, Fair Value [Abstract]
Within 1 year	381
After 1 year through 5 years	4,864
After 5 years through 10 years	27,032
After 10 years	248,738
Other	496,193
Fair value	$ 777,208	$ 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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