Stock Incentive Plan - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of authorized stock for stock incentive plan (in shares)	350,000
Stock-based compensation expense	$ 196	$ 253
Shares issued upon exercise of stock options (in shares)	1,723	0
Shares withheld for stock option exercises and related income taxes, amount withheld	$ 49
Options granted (in shares)	0	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation, options, contractual term	10 years
Stock incentive plan vesting period, years	3 years
Stock-based compensation expense	$ 32	$ 76
Cashless Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from stock option exercises	$ 66
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plan vesting period, years	3 years
Stock-based compensation expense	$ 164	$ 177
Restricted units granted (in shares)	0	0

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Withheld Shares For Company Expenses

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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.

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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.

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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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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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

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Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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