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Securities - Available-for-sale Securities in Continuous Loss Position (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, fair value, less than 12 months	$ 94,685	$ 67,058
Available-for-sale, gross unrealized losses, less than 12 months	(2,936)	(475)
Available-for-sale, fair value, 12 months or greater	49,116	50,580
Available-for-sale, gross unrealized losses, 12 months or greater	(2,112)	(1,312)
Securities available for sale	143,801	117,638
Available-for-sale, gross unrealized losses, total	(5,048)	(1,787)
U.S. Government-sponsored enterprises (GSEs) [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, fair value, less than 12 months	14,425	1,358
Available-for-sale, gross unrealized losses, less than 12 months	(575)	(1)
Available-for-sale, fair value, 12 months or greater	13,559	13,420
Available-for-sale, gross unrealized losses, 12 months or greater	(568)	(431)
Securities available for sale	27,984	14,778
Available-for-sale, gross unrealized losses, total	(1,143)	(432)
Municipal securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, fair value, less than 12 months	31,075	3,418
Available-for-sale, gross unrealized losses, less than 12 months	(648)	(43)
Available-for-sale, fair value, 12 months or greater	2,559	2,112
Available-for-sale, gross unrealized losses, 12 months or greater	(181)	(104)
Securities available for sale	33,634	5,530
Available-for-sale, gross unrealized losses, total	(829)	(147)
Other debt securities [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, fair value, less than 12 months	0	950
Available-for-sale, gross unrealized losses, less than 12 months	0	(24)
Available-for-sale, fair value, 12 months or greater	924	0
Available-for-sale, gross unrealized losses, 12 months or greater	(52)	0
Securities available for sale	924	950
Available-for-sale, gross unrealized losses, total	(52)	(24)
Mortgage-backed securities (GSEs) [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale, fair value, less than 12 months	49,185	61,332
Available-for-sale, gross unrealized losses, less than 12 months	(1,713)	(407)
Available-for-sale, fair value, 12 months or greater	32,074	35,048
Available-for-sale, gross unrealized losses, 12 months or greater	(1,311)	(777)
Securities available for sale	81,259	96,380
Available-for-sale, gross unrealized losses, total	$ (3,024)	$ (1,184)

X

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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.

+ References

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+ References

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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 unrealized loss position.

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+ References

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