Benefit Plans, Valuation, Stock-Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Service Share-based Compensation, Non-vested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	$ 173	$ 150	$ 224
Stock Options [Member]
Employee Service Share-based Compensation, Non-vested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Options maximum term	5 years
Unrecognized stock-based compensation expense related to non-vested stock options	$ 38
Unrecognized compensation expense, period of recognition	1 year 7 months 2 days
Restricted Shares Units [Member]
Activity for Performance Based Awards [Roll Forward]
Balance, Beginning of period (in shares)	213,100
New awards granted (in shares)	104,424
Forfeited awards (in shares)	(13,350)
Awards settled (in shares)	(85,747)
Balance, End of period (in shares)	218,427	213,100
Employee Service Share-based Compensation, Non-vested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	$ 458	$ 633	610
Options maximum term	3 years
Unrecognized stock-based compensation expense	$ 1,000
Unrecognized compensation expense, period of recognition	29 months
Additional Disclosures [Abstract]
Shares vested after term	100.00%
Liability related to awards	$ 526	$ 749
Performance Share Units [Member]
Activity for Performance Based Awards [Roll Forward]
Balance, Beginning of period (in shares)	370,100
New awards granted (in shares)	138,643
Forfeited awards (in shares)	(17,774)
Awards settled (in shares)	(82,076)
Balance, End of period (in shares)	408,893	370,100
Employee Service Share-based Compensation, Non-vested Awards, Total Compensation Cost Not yet Recognized [Abstract]
Stock based compensation expense	$ 644	$ 1,200	$ 23
Options maximum term	3 years
Unrecognized stock-based compensation expense	$ 1,600
Unrecognized compensation expense, period of recognition	27 months
Additional Disclosures [Abstract]
Shares vested after term	100.00%
Liability related to awards	$ 1,700	$ 1,500

The percentage of shares awarded that will vest after the stated term.

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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- References

No definition available.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (i)
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

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-Publisher FASB
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-SubTopic 10
-Section 45
-Paragraph 28
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

No definition available.

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- Definition

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

+ 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
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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

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

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

+ References

No definition available.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
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