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Capital Transactions - Narrative (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2015 | Dec. 31, 2018 | Dec. 31, 2012
2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares authorized under the plan (in shares) |  |  |  |  |  |  | 1,500,000
Additional number of shares authorized under the plan (in shares) |  |  |  |  | 1,500,000 |  |
Maximum | 2009 Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares authorized under the plan (in shares) | 400,000 |  | 400,000 |  |  |  |
Stock options |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Options outstanding (in shares) | 940,000 |  | 940,000 |  |  | 1,114,000 |
Aggregate intrinsic value, outstanding | $ 300,000 |  | $ 300,000 |  |  | $ 200,000 |
Exercised (in shares) |  |  | 1,000 | 69,000 |  |  |
Exercised (in dollars per share) |  |  | $ 2.35 | $ 5.11 |  |  |
Aggregate intrinsic values of options exercised |  |  | $ 10,000 | $ 400,000 |  |  |
Tax benefit from the exercise of stock options |  |  | 3,000 | 100,000 |  |  |
Time-based stock options |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based compensation expense | $ 0 | $ 100,000 | $ 0 | 100,000 |  |  |
Time-based stock options | Maximum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  | 48 months |  |  |  |
Performance based stock options operating income margins |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Operating income margin, one (as a percent) |  |  | 6.00% |  |  |  |
Operating income margin, two (as a percent) |  |  | 8.00% |  |  |  |
Operating income margin, three (as a percent) |  |  | 10.00% |  |  |  |
Unvested stock options outstanding (in shares) | 0 |  | 0 |  |  | 0 |
Performance based stock options operating income margins | Minimum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award performance period |  |  | 1 year |  |  |  |
Performance based stock options operating income margins | Maximum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award performance period |  |  | 1 year 3 months |  |  |  |
RSUs |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Award performance period |  |  | 3 years |  |  |  |
Share-based compensation expense | $ 500,000 | 500,000 | $ 600,000 | $ 1,000,000 |  |  |
Discount for lack of marketability |  |  | 13.40% |  |  |  |
Expected volatility (as a percent) |  |  | 50.00% |  |  |  |
Unrecognized share-based compensation expense | $ 2,100,000 |  | $ 2,100,000 |  |  | $ 1,800,000 |
Weighted-average period over which the remaining compensation cost is expected to be recognized |  |  | 11 months |  |  |  |
Minimum withholding requirements (in shares) |  |  | 23,000 | 40,000 |  |  |
RSUs | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Granted (in shares) |  |  | 333,000 |  |  |  |
RSUs | Minimum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Risk-free interest rate (as a percent) |  |  | 2.10% |  |  |  |
RSUs | Minimum | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  | 12 months |  |  |  |
RSUs | Maximum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Risk-free interest rate (as a percent) |  |  | 2.90% |  |  |  |
RSUs | Maximum | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  | 36 months |  |  |  |
RSUs | Director | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Restriction period for issuance of shares |  |  | 2 years |  |  |  |
Nonvested subject to restriction period (in shares) | 78,000 |  | 78,000 |  |  | 80,000 |
Time-Based Restricted Stock Units (RSUs) | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  | 3 years |  |  |  |
Weighted-average grant date fair value (in dollars per share) |  |  | $ 8.59 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share-based compensation expense | $ 100,000 | $ 0 | $ 200,000 | $ 0 |  |  |
Share based compensation potential compensation expense to be recognized | 1,100,000 |  | $ 1,100,000 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Weighted-average grant date fair value (in dollars per share) |  |  | $ 4.38 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) | Maximum |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Share based compensation potential compensation expense to be recognized | $ 2,100,000 |  | $ 2,100,000 |  |  |  |
Performance-Based Restricted Stock Units (RSUs) | Net Sales and Operating Income Targets | 2012 Stock Incentive Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period |  |  | 3 years |  |  |  |

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