SECURITIES - Held to Maturity Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Held to maturity:
Less than 12 months, Estimated Fair Value	$ 8,115	$ 8,286
Less than 12 months, Gross Unrealized losses	(10)	(26)
Greater than 12 months, Estimated Fair Value	26,687	116,491
Greater than 12 months, Gross Unrealized losses	(392)	(3,802)
State and municipal obligations
Held to maturity:
Less than 12 months, Estimated Fair Value	0	8,286
Less than 12 months, Gross Unrealized losses	0	(26)
Greater than 12 months, Estimated Fair Value	402	22,142
Greater than 12 months, Gross Unrealized losses	0	(250)
U.S. GSE residential mortgage-backed securities
Held to maturity:
Less than 12 months, Estimated Fair Value	0	0
Less than 12 months, Gross Unrealized losses	0	0
Greater than 12 months, Estimated Fair Value	7,580	9,352
Greater than 12 months, Gross Unrealized losses	(58)	(336)
U.S. GSE residential collateralized mortgage obligations
Held to maturity:
Less than 12 months, Estimated Fair Value	0	0
Less than 12 months, Gross Unrealized losses	0	0
Greater than 12 months, Estimated Fair Value	9,090	40,665
Greater than 12 months, Gross Unrealized losses	(264)	(1,130)
U.S. GSE commercial mortgage-backed securities
Held to maturity:
Less than 12 months, Estimated Fair Value	0	0
Less than 12 months, Gross Unrealized losses	0	0
Greater than 12 months, Estimated Fair Value	5,187	16,205
Greater than 12 months, Gross Unrealized losses	(15)	(620)
U.S. GSE commercial collateralized mortgage obligations
Held to maturity:
Less than 12 months, Estimated Fair Value	8,115	0
Less than 12 months, Gross Unrealized losses	(10)	0
Greater than 12 months, Estimated Fair Value	4,428	28,127
Greater than 12 months, Gross Unrealized losses	$ (55)	$ (1,466)

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

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- References

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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for less than 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27290-111563

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27337-111563

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for less than 12 months.

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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity), in continuous unrealized loss position for 12 months or longer.

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