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Stockholders' Equity (Narrative) (Details) - USD ($) | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 09, 2015 | Dec. 04, 2013
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized (shares) | 20,000,000 |  |  |  | 20,000,000 |  |  |  | 20,000,000 | 20,000,000 |  |  |
Common stock, issued shares (shares) | 11,115,779 |  |  |  | 11,115,779 |  |  |  | 11,115,779 | 11,115,779 |  |  |
Common stock, par value (usd per share) | $ 0.01 |  |  |  | $ 0.01 |  |  |  | $ 0.01 | $ 0.01 |  |  |
Dividends paid per common share (usd per share) | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0.04 | $ 0.04 | $ 0.04 | $ 0.00 | $ 0.12 | $ 0.16 |  |
Preferred stock shares authorized (shares) | 5,000,000 |  |  |  | 5,000,000 |  |  |  | 5,000,000 | 5,000,000 |  |  |
Preferred stock issued (shares) | 0 |  |  |  | 0 |  |  |  | 0 | 0 |  |  |
Preferred stock par value (usd per share) | $ 0 |  |  |  | $ 0 |  |  |  | $ 0 | $ 0 |  |  |
Repurchased common stock (shares) |  |  |  |  |  |  |  |  | 0 | 5,000 | 80,512 |  |
Purchase of common shares for treasury |  |  |  |  |  |  |  |  |  | $ 67,000 | $ 1,587,000 |  |
Shares paid for tax withholding (shares) |  |  |  |  |  |  |  |  | 7,277 | 20,186 |  |  |
Adjustments related to tax withholding |  |  |  |  |  |  |  |  | $ 103,000 | $ 275,000 |  |  |
Cash dividends on common stock paid to shareholders |  |  |  |  |  |  |  |  | 0 | $ 1,244,000 | $ 1,656,000 |  |
December 2013 Share Repurchase Program |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Stock repurchase program authorized amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000,000
December 2015 Share Repurchase Program |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Stock repurchase program authorized amount |  |  |  |  |  |  |  |  |  |  |  | $ 30,000,000 |
Shares remaining for repurchase, value | $ 29,933,000 |  |  |  |  |  |  |  | $ 29,933,000 |  |  |  |

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