Benefit Plans - Restricted Stock (Details)	12 Months Ended
Dec. 31, 2019 $ / shares shares
Restricted Stock Units
Restricted Stock Awards (in shares)
Nonvested at beginning of period \| shares	75,554
Granted \| shares	74,698
Vested \| shares	(36,218)
Forfeited \| shares	(6,790)
Nonvested at end of period \| shares	107,244
Weighted-Average Grant Date Fair Value Per Share (in dollars per share)
Weighted-Average Grant Date Fair Value Per Share Nonvested, Beginning Balance (in dollars per share) \| $ / shares	$ 35.34
Weighted-Average Grant Date Fair Value Per Share Granted (in dollars per share) \| $ / shares	24.61
Weighted-Average Grant Date Fair Value Per Share Vested (in dollars per share) \| $ / shares	33.08
Weighted-Average Grant Date Fair Value Per Share Forfeited (in dollars per share) \| $ / shares	29.10
Weighted-Average Grant Date Fair Value Per Share Nonvested, Ending Balance (in dollars per share) \| $ / shares	$ 29.03
Restricted Stock Awards
Restricted Stock Awards (in shares)
Nonvested at beginning of period \| shares	1,666
Granted \| shares	11,742
Vested \| shares	(13,408)
Forfeited \| shares	0
Nonvested at end of period \| shares	0
Weighted-Average Grant Date Fair Value Per Share (in dollars per share)
Weighted-Average Grant Date Fair Value Per Share Nonvested, Beginning Balance (in dollars per share) \| $ / shares	$ 24.44
Weighted-Average Grant Date Fair Value Per Share Granted (in dollars per share) \| $ / shares	24.62
Weighted-Average Grant Date Fair Value Per Share Vested (in dollars per share) \| $ / shares	24.60
Weighted-Average Grant Date Fair Value Per Share Forfeited (in dollars per share) \| $ / shares	0.00
Weighted-Average Grant Date Fair Value Per Share Nonvested, Ending Balance (in dollars per share) \| $ / shares	$ 0.00
Deferred Stock Units
Restricted Stock Awards (in shares)
Nonvested at beginning of period \| shares	0
Granted \| shares	11
Vested \| shares	(11)
Forfeited \| shares	0
Nonvested at end of period \| shares	0
Weighted-Average Grant Date Fair Value Per Share (in dollars per share)
Weighted-Average Grant Date Fair Value Per Share Nonvested, Beginning Balance (in dollars per share) \| $ / shares	$ 0.00
Weighted-Average Grant Date Fair Value Per Share Granted (in dollars per share) \| $ / shares	21.88
Weighted-Average Grant Date Fair Value Per Share Vested (in dollars per share) \| $ / shares	21.88
Weighted-Average Grant Date Fair Value Per Share Forfeited (in dollars per share) \| $ / shares	0.00
Weighted-Average Grant Date Fair Value Per Share Nonvested, Ending Balance (in dollars per share) \| $ / shares	$ 0.00

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.

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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).

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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).

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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.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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

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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.

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