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MARKETABLE SECURITIES - Narrative (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) Position security	Dec. 31, 2020 USD ($)
Investments Debt And Equity Securities [Abstract]
Allowance for credit losses for available for sale debt securities	$ 0
Other than temporary impairment losses on debt securities related to credit losses		$ 0
Number of investment in an unrealized loss position | Position	16
Percentage of unrealized loss exceeds book value	20.00%
Number of securities other than agencies amount | security	0
Fair value of securities pledged as collateral	$ 317,293,000	$ 314,962,000
Number of securities sold | security	0

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Number of securities held amount greater than ten percentage of share holders equity.

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Amount of allowance for credit loss on 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

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