Share-Based Compensation - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	85,425	44,700
Treasury Stock Reissued Shares For Director Grants	9,950	10,150	10,200
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 950,000	$ 963,000	$ 801,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	825
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	1,125
Allocated Share-based Compensation Expense	$ 2,839,000
2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares authorized for delivery upon the exercise of incentive stock options	600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Period Increase (Decrease)	473,725
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	41,550	23,025	21,975
Allocated Share-based Compensation Expense	$ 1,864,000	$ 865,000	$ 458,000
Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Treasury Stock Reissued Shares For Director Grants	9,950	10,150	10,200
Allocated Share-based Compensation Expense	$ 1,864,000	$ 865,000	$ 458,000
Expense to be paid next twelve months [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	1,193,000
Expense to be paid Year Two [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	1,072,000
Expense to be paid Year Three [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	491,000
Expense to be paid Year Four [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 83,000

Common Shares Authorized for Delivery Upon the Exercise of Incentive Stock Options

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Treasury Stock Reissued Shares For Director Grants

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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The increase or decrease in number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding, including vested options.

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- Definition

Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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