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Stock-Based Compensation (Stock Options Narrative) (Details) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 16, 2009 shares | Apr. 30, 2015 Option $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares | Dec. 31, 2014 USD ($) $ / shares | Dec. 31, 2013 USD ($) $ / shares | Dec. 31, 1998 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of options granted | Option |  | 1 |  |  |  |
Options granted in period (in shares) |  |  | 50,000 |  |  |
Options granted in period, weighted average exercise price (in dollars per share) | $ / shares |  |  | $ 22.90 |  |  |
Weighted average grant date fair value of options granted (in dollars per share) | $ / shares |  |  | $ 10.33 | $ 16.56 | $ 10.30 |
Total intrinsic value of options exercised | $ |  |  | $ 481 | $ 48 | $ 458 |
Proceeds from exercise of stock options | $ |  |  | 776 | 59 | 829 |
Unrecognized compensation cost related to stock options | $ |  |  | 722 |  |  |
Stock Options |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Share-based compensation expense | $ |  |  | $ 601 | $ 426 | $ 198 |
Unrecognized compensation cost related to stock options, weighted average period for recognition |  |  | 3 years |  |  |
Stock Options | 1998 Stock Option Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period |  |  | 3 years |  |  |
Award expiration period |  |  | 10 years |  |  |
Stock Options | Common Stock | 1998 Stock Option Plan |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of shares authorized | 750,000 |  |  |  |  | 550,000
Additional shares authorized | 200,000 |  |  |  |  |
Number of shares available for grant |  |  | 93,419 |  |  |
Non-Executive Employees |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Award vesting period |  | 3 years |  |  |  |
Options granted in period (in shares) |  | 50,000 |  |  |  |
Options granted in period, weighted average exercise price (in dollars per share) | $ / shares |  | $ 22.90 |  |  |  |

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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) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F + Details
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- Definition The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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