Stock Compensation Plans - Restricted stock grants (Details)	3 Months Ended
Mar. 31, 2020 $ / shares shares
Restricted Stock Units (RSUs) [Member]
Shares, Unvested at January 1, 2020 \| shares	158,470
Shares, Vested \| shares	(86,050)
Shares, Forfeited \| shares	(26,291)
Shares, Unvested at March 31, 2020 \| shares	46,129
Weighted -Average Grant Date Fair Value, Unvested at January 1, 2020 \| $ / shares	$ 25.72
Weighted-Average Grant Date Fair Value, Vested \| $ / shares	25.48
Weighted-Average Grant Date Fair Value, Forfeited \| $ / shares	25.58
Weighted-Average Grant Date Fair Value, Unvested at March 31, 2020 \| $ / shares	$ 26.24
Stock Grants [Member]
Shares, Unvested at January 1, 2020 \| shares	48,545
Shares, Granted \| shares	13,349
Shares, Vested \| shares	(1,244)
Shares, Unvested at March 31, 2020 \| shares	60,650
Weighted -Average Grant Date Fair Value, Unvested at January 1, 2020 \| $ / shares	$ 27.49
Weighted-Average Grant Date Fair Value, Granted \| $ / shares	25.75
Weighted-Average Grant Date Fair Value, Vested \| $ / shares	28.60
Weighted-Average Grant Date Fair Value, Unvested at March 31, 2020 \| $ / shares	$ 27.09

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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-Publisher FASB
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