Investment Securities - Securities Held to Maturity in an Unrealized Loss Position (Details) - Mortgage-backed securities - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value
Less than 12 Months	$ 1,315	$ 2,756
12 Months or Longer	7,123	3,866
Total	8,438	6,622
Unrealized Losses
Less than 12 Months	(4)	(25)
12 Months or Longer	(242)	(61)
Total	$ (246)	$ (86)

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
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- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Fair value of investment in debt security measured at amortized cost (held-to-maturity), in unrealized loss position.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
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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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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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