MARKETABLE SECURITIES - Securities in Continuous Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Gross Unrealized Losses
Less Than 12 Months	$ (30,440)	$ (74)
12 Months or Longer	973	81
Total	(31,413)	(155)
Estimated Fair Value
Less Than 12 Months	581,752	10,688
12 Months or Longer	5,627	2,996
Total	587,379	13,684
Gross Unrealized Losses
Less Than 12 Months	(15,173)	(2,414)
12 Months or Longer	(2,690)	(396)
Total	(17,863)	(2,810)
Estimated Fair Value
Less Than 12 Months	177,546	205,928
12 Months or Longer	14,774	11,317
Total	192,320	217,245
U.S. government agencies
Gross Unrealized Losses
Less Than 12 Months	(1,181)
12 Months or Longer	0
Total	(1,181)
Estimated Fair Value
Less Than 12 Months	8,830
12 Months or Longer	0
Total	8,830
Gross Unrealized Losses
Less Than 12 Months		(42)
12 Months or Longer		0
Total		(42)
Estimated Fair Value
Less Than 12 Months		9,971
12 Months or Longer
Total		9,971
Corporate bonds
Gross Unrealized Losses
Less Than 12 Months	(1,455)	(85)
12 Months or Longer	0	0
Total	(1,455)	(85)
Estimated Fair Value
Less Than 12 Months	33,574	11,418
12 Months or Longer	0
Total	33,574	11,418
Mortgage-backed securities
Gross Unrealized Losses
Less Than 12 Months	(11,834)	(37)
12 Months or Longer	973	0
Total	(12,807)	(37)
Estimated Fair Value
Less Than 12 Months	104,888	2,916
12 Months or Longer	5,627	0
Total	110,515	2,916
Gross Unrealized Losses
Less Than 12 Months	(12,272)	(1,383)
12 Months or Longer	(2,690)	(396)
Total	(14,962)	(1,779)
Estimated Fair Value
Less Than 12 Months	113,242	144,367
12 Months or Longer	14,774	11,317
Total	128,016	155,684
Collateralized mortgage obligations
Gross Unrealized Losses
Less Than 12 Months	(6,147)
12 Months or Longer	0
Total	(6,147)
Estimated Fair Value
Less Than 12 Months	43,104
12 Months or Longer	0
Total	43,104
Gross Unrealized Losses
Less Than 12 Months	(1,384)	(904)
12 Months or Longer	0	0
Total	(1,384)	(904)
Estimated Fair Value
Less Than 12 Months	22,706	40,172
12 Months or Longer	0	0
Total	22,706	40,172
Municipal securities
Gross Unrealized Losses
Less Than 12 Months	(8,446)	(37)
12 Months or Longer	0	81
Total	(8,446)	(118)
Estimated Fair Value
Less Than 12 Months	103,252	7,772
12 Months or Longer	0	2,996
Total	103,252	$ 10,768
Gross Unrealized Losses
Less Than 12 Months	(62)
12 Months or Longer	0
Total	(62)
Estimated Fair Value
Less Than 12 Months	8,024
12 Months or Longer	0
Total	8,024
US Treasury Securities [Member]
Gross Unrealized Losses
Less Than 12 Months	(2,832)
12 Months or Longer	0
Total	(2,832)
Estimated Fair Value
Less Than 12 Months	321,678
12 Months or Longer	0
Total	$ 321,678