MARKETABLE SECURITIES - Securities in Continuous Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Gross Unrealized Losses
Less Than 12 Months	$ (949)	$ (95)
12 Months or Longer	(44)	(1)
Total	(993)	(96)
Estimated Fair Value
Less Than 12 Months	94,031	28,268
12 Months or Longer	3,276	106
Total	97,307	28,374
Gross Unrealized Losses
Less Than 12 Months	(184)
12 Months or Longer	0
Total	184
Estimated Fair Value
Less Than 12 Months	7,387
12 Months or Longer	0
Total	7,387
Corporate bonds
Gross Unrealized Losses
Less Than 12 Months	(92)	(8)
12 Months or Longer	0
Total	(92)	(8)
Estimated Fair Value
Less Than 12 Months	7,678	2,493
12 Months or Longer	0
Total	7,678	2,493
Mortgage-backed securities
Gross Unrealized Losses
Less Than 12 Months	(803)	(87)
12 Months or Longer	(44)
Total	(847)	(87)
Estimated Fair Value
Less Than 12 Months	68,150	25,775
12 Months or Longer	3,276
Total	71,426	25,775
Gross Unrealized Losses
Less Than 12 Months	(37)
12 Months or Longer	0
Total	37
Estimated Fair Value
Less Than 12 Months	3,006
12 Months or Longer	0
Total	3,006
Collateralized mortgage obligations
Gross Unrealized Losses
Less Than 12 Months	(54)
12 Months or Longer	0	(1)
Total	(54)	(1)
Estimated Fair Value
Less Than 12 Months	18,203
12 Months or Longer	0	106
Total	18,203	$ 106
Municipal securities
Gross Unrealized Losses
Less Than 12 Months	(147)
12 Months or Longer	0
Total	147
Estimated Fair Value
Less Than 12 Months	4,381
12 Months or Longer	0
Total	$ 4,381