Stockholders' Equity - Restricted Stock and Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock issued	123,564	127,688
Value of restricted stock issued	$ 612	$ 351
Weighted average estimated fair value of restricted stock issued	$ 4.93	$ 3.79
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock issued	184,454	34,988
Value of restricted stock issued	$ 909	$ 133
Vesting terms (years)	1 year

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 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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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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