Securities - Narrative (Details) $ in Thousands	Sep. 30, 2017 USD ($) Security	Dec. 31, 2016 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Carrying value of securities pledged as collateral \| $	$ 177,259	$ 134,763
U.S. Government and agencies
Schedule of Available-for-sale Securities [Line Items]
Number of available-for-sale securities with unrealized losses	56
Percentage of amortized cost	4.00%
Number of available-for-sale securities, in continuous loss positions for 12 months or more	9
Schedule of Held-to-maturity Securities [Line Items]
Number of held to maturity securities with unrealized losses	8
Percentage of amortized cost	1.00%
Number of held to maturity securities, in continuous loss position for 12 months or more	1
Mortgage-backed securities, residential
Schedule of Available-for-sale Securities [Line Items]
Number of available-for-sale securities, not in continuous loss position for 12 months or more	8
Percentage of amortized cost	1.00%
Schedule of Held-to-maturity Securities [Line Items]
Number of held to maturity securities with unrealized losses	13
Percentage of amortized cost	2.00%
Number of held to maturity securities, in continuous loss position for 12 months or more	1
State and municipal
Schedule of Available-for-sale Securities [Line Items]
Number of available-for-sale securities with unrealized losses	9
Percentage of amortized cost	2.00%
Number of available-for-sale securities, in continuous loss positions for 12 months or more	3
CRA Mutual Fund
Schedule of Available-for-sale Securities [Line Items]
Percentage of amortized cost	1.00%

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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Held-to-maturity, Securities in Unrealized Loss Positions, Unrealized Losses as Percentage of Amortized Cost

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Number of investment positions in available-for-sale investments in a continuous unrealized loss position for less than one year or normal operating cycle, if longer, for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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

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Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.

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