SECURITIES - Held to Maturity Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Held to maturity:
Less than 12 months, Estimated Fair Value	$ 50,635	$ 49,527
Less than 12 months, Gross Unrealized losses	(1,229)	(404)
Greater than 12 months, Estimated Fair Value	81,452	60,518
Greater than 12 months, Gross Unrealized losses	(4,314)	(1,870)
State and municipal obligations
Held to maturity:
Less than 12 months, Estimated Fair Value	28,515	7,709
Less than 12 months, Gross Unrealized losses	(564)	(57)
Greater than 12 months, Estimated Fair Value	2,466	1,009
Greater than 12 months, Gross Unrealized losses	(100)	(7)
U.S. GSE residential mortgage-backed securities
Held to maturity:
Less than 12 months, Estimated Fair Value		1,359
Less than 12 months, Gross Unrealized losses		(16)
Greater than 12 months, Estimated Fair Value	9,561	9,804
Greater than 12 months, Gross Unrealized losses	(481)	(245)
U.S. GSE residential collateralized mortgage obligations
Held to maturity:
Less than 12 months, Estimated Fair Value	16,116	21,329
Less than 12 months, Gross Unrealized losses	(527)	(94)
Greater than 12 months, Estimated Fair Value	28,963	21,112
Greater than 12 months, Gross Unrealized losses	(1,239)	(572)
U.S. GSE commercial mortgage-backed securities
Held to maturity:
Less than 12 months, Estimated Fair Value	5,946	8,789
Less than 12 months, Gross Unrealized losses	(138)	(121)
Greater than 12 months, Estimated Fair Value	12,366	8,303
Greater than 12 months, Gross Unrealized losses	(835)	(317)
U.S. GSE commercial collateralized mortgage obligations
Held to maturity:
Less than 12 months, Estimated Fair Value	58	10,341
Less than 12 months, Gross Unrealized losses		(116)
Greater than 12 months, Estimated Fair Value	28,096	20,290
Greater than 12 months, Gross Unrealized losses	$ (1,659)	$ (729)

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=82897076&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=82897076&loc=d3e27290-111563

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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.

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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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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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