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Securities - Narrative (Details)	Mar. 31, 2019 USD ($) Security	Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items]
Carrying value of securities pledged as collateral as required by law on public and trust deposits, repurchase agreements, and for other purposes | $	$ 164,002,000	$ 165,792,000
U.S. Government and agencies
Debt Securities, Available-for-sale [Line Items]
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	4.00%
Available for sale securities in unrealized loss positions for 12 months or more	48
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	1.00%
Held to maturity securities in unrealized loss positions for 12 months or more	5
Mortgage-backed securities, residential
Debt Securities, Available-for-sale [Line Items]
Available for sale securities in unrealized loss positions	22
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	15.00%
Available for sale securities in unrealized loss positions for 12 months or more	20
Schedule of Held-to-maturity Securities [Line Items]
Held to maturity securities in unrealized loss positions	27
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	2.00%
Held to maturity securities in unrealized loss positions for 12 months or more	24
State and municipal
Debt Securities, Available-for-sale [Line Items]
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed)	2.00%
Available for sale securities in unrealized loss positions for 12 months or more	7

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- Definition

Available-for-sale, Securities in Unrealized Loss Positions, Unrealized Losses as Percentage of Amortized Cost

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Held-to-maturity, Number of Securities in Continuous Loss Positions for 12 Months or More

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ 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 (b)(3)
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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
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