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Equity Compensation Plans - Options (Details) - USD ($) |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2009 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | May 31, 2016 | Dec. 31, 2015
Equity Compensation Plans |  |  |  |  |  |  |
Term of stock options granted | 10 years |  |  |  |  |  |
Vesting period | 3 years |  |  |  |  |  |
Shares |  |  |  |  |  |  |
Exercised (in shares) |  |  | $ (33,000) |  | $ (11,000) |  |
2009 Plan |  |  |  |  |  |  |
Equity Compensation Plans |  |  |  |  |  |  |
Granted (in shares) |  | 16,500 |  |  |  |  |
Exercised (in shares) |  |  | 4,500 | 0 | 1,500 |  |
Shares |  |  |  |  |  |  |
Ending outstanding (in shares) | 4,500 |  | 4,500 |  |  |  |
Stock options |  |  |  |  |  |  |
Equity Compensation Plans |  |  |  |  |  |  |
Total unrecognized compensation cost | $ 0 |  | $ 0 |  |  |  |
Shares |  |  |  |  |  |  |
Beginning outstanding (in shares) |  |  | 9,000 |  |  |  |
Exercised (in shares) |  |  | $ (4,500) |  |  |  |
Ending outstanding (in shares) | 4,500 |  | 4,500 | 9,000 |  |  |
Exercisable at end of period (in shares) | 4,500 |  | 4,500 |  |  |  |
Weighted Average Exercise Price |  |  |  |  |  |  |
Beginning outstanding (in dollars per share) |  |  | $ 7.49 |  |  |  |
Exercised (in dollars per share) |  |  | 7.49 |  |  |  |
Ending outstanding (in dollars per share) | $ 7.49 |  | 7.49 | $ 7.49 |  |  |
Exercisable at end of period (in dollars per share) | $ 7.49 |  | $ 7.49 |  |  |  |
Weighted Average Remaining Contractual Term (years) |  |  |  |  |  |  |
Ending outstanding (in years) |  |  | 1 month 6 days | 1 year 1 month 6 days |  |  |
Exercisable at end of period |  |  | 1 month 6 days |  |  |  |
Aggregate Intrinsic Value |  |  |  |  |  |  |
Exercised (in dollars) |  |  | $ (27,000) |  | $ (3,000) |  |
Ending outstanding (in dollars) | $ 25,000 |  | 25,000 | $ 55,000 |  |  |
Exercisable at the end of the period (in dollars) | $ 25,000 |  | $ 25,000 |  |  |  |
Stock options | 2014 Plan |  |  |  |  |  |  |
Equity Compensation Plans |  |  |  |  |  |  |
Number of shares authorized |  |  |  |  |  | 975,000 | 375,000

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- Definition Unrecognized cost of unvested options awarded to employees as compensation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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