SECURITIES - Available for Sale Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Available for sale:
Less than 12 months, Estimated Fair Value	$ 95,818	$ 175,474
Less than 12 months, Gross Unrealized Losses	(614)	(778)
Greater than 12 months, Estimated Fair Value	33,120	214,908
Greater than 12 months, Gross Unrealized Losses	(1,788)	(4,619)
U.S. Treasury securities
Available for sale:
Less than 12 months, Estimated Fair Value		50,822
Less than 12 months, Gross Unrealized Losses		(11)
U.S. GSE securities
Available for sale:
Less than 12 months, Estimated Fair Value		0
Less than 12 months, Gross Unrealized Losses		0
Greater than 12 months, Estimated Fair Value		4,995
Greater than 12 months, Gross Unrealized Losses		(5)
State and municipal obligations
Available for sale:
Less than 12 months, Estimated Fair Value	5,310	4,982
Less than 12 months, Gross Unrealized Losses	(10)	(42)
Greater than 12 months, Estimated Fair Value		76
Greater than 12 months, Gross Unrealized Losses		(1)
U.S. GSE residential mortgage-backed securities
Available for sale:
Less than 12 months, Estimated Fair Value		2,935
Less than 12 months, Gross Unrealized Losses		(30)
Greater than 12 months, Estimated Fair Value	152	39,617
Greater than 12 months, Gross Unrealized Losses	(6)	(438)
U.S. GSE residential collateralized mortgage obligations
Available for sale:
Less than 12 months, Estimated Fair Value	55,832	81,377
Less than 12 months, Gross Unrealized Losses	(226)	(480)
Greater than 12 months, Estimated Fair Value		93,403
Greater than 12 months, Gross Unrealized Losses		(984)
U.S. GSE commercial mortgage-backed securities
Available for sale:
Less than 12 months, Estimated Fair Value	14,994	6,648
Less than 12 months, Gross Unrealized Losses	(253)	(70)
Greater than 12 months, Estimated Fair Value		0
Greater than 12 months, Gross Unrealized Losses		0
U.S. GSE commercial collateralized mortgage obligations
Available for sale:
Less than 12 months, Estimated Fair Value	11,755	28,710
Less than 12 months, Gross Unrealized Losses	(52)	(145)
Greater than 12 months, Estimated Fair Value		9,614
Greater than 12 months, Gross Unrealized Losses		(144)
Other asset backed securities
Available for sale:
Less than 12 months, Estimated Fair Value		0
Less than 12 months, Gross Unrealized Losses		0
Greater than 12 months, Estimated Fair Value	3,450	23,401
Greater than 12 months, Gross Unrealized Losses	(300)	(849)
Corporate
Available for sale:
Less than 12 months, Estimated Fair Value	7,927	0
Less than 12 months, Gross Unrealized Losses	(73)	0
Greater than 12 months, Estimated Fair Value	29,518	43,802
Greater than 12 months, Gross Unrealized Losses	$ (1,482)	$ (2,198)

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 5
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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