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Stock - Based Compensation - Narrative (Details) - USD ($) |  |  |  |  |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 18, 2020 | Nov. 10, 2020 | Jun. 30, 2020 | Feb. 05, 2020 | May 16, 2019 | Feb. 06, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | May 17, 2018 | Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares authorized (in shares) |  |  |  |  |  |  | 500,000 |  |  |  |
Options available (in shares) |  |  |  |  |  |  | 0 |  |  |  |
Compensation expense |  |  |  |  |  |  | $ 1,800,000 | $ 2,100,000 |  |  |
(Benefit from) provision for income taxes |  |  |  |  |  |  | $ 200,000 | $ 400,000 |  |  |
Exercised (in shares) |  |  |  |  |  |  |  | 3,628 |  |  |
Options exercisable (in shares) |  |  |  |  |  |  | 86,531 |  |  |  |
Options exercisable, weighted average exercise price (in dollars per share) |  |  |  |  |  |  | $ 13.77 |  |  |  |
Share-based compensation expense |  |  |  |  |  |  | $ 1,791,000 | $ 2,091,000 |  |  |
Issuance of shares of common stock from the treasury (in shares) |  |  |  |  |  |  | 194,082 | 162,869 |  |  |
Stock Options |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Options available (in shares) |  |  |  |  |  |  | 31,782 | 155,845 | 155,845 |  |
Nonvested award, cost not yet recognized, period for recognition |  |  |  |  |  |  | 2 years 1 month 20 days |  |  |  |
Exercised (in shares) |  |  |  |  |  |  | 0 | 3,628 |  |  |
Option exercises, aggregate exercise price |  |  |  |  |  |  |  | $ 45,734 |  |  |
Options exercisable (in shares) |  |  |  |  |  |  | 86,531 | 51,745 |  |  |
Options exercisable, weighted average exercise price (in dollars per share) |  |  |  |  |  |  | $ 13.77 | $ 14.13 |  |  |
Share-based compensation expense |  |  |  |  |  |  | $ 400,000 | $ 31,186 |  |  |
Total unrecognized compensation cost |  |  |  |  |  |  | $ 200,000 |  |  |  |
Stock Awards |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Equity instruments other options, grants in period (in shares) |  |  |  |  |  |  | 81,233 | 84,734 |  |  |
Weighted average price, common shares (in dollars per share) |  |  |  |  |  |  | $ 12.87 | $ 11.76 |  |  |
Stock Awards | Share-based Payment Arrangement, Tranche One |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  | 66.66% |  |  |  |  |  |  |  |  |
Vesting period |  | 1 year |  |  |  |  |  |  |  |  |
Stock Awards | Share-based Payment Arrangement, Tranche Two |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  | 33.33% |  |  |  |  |  |  |  |  |
Vesting period |  | 18 months |  |  |  |  |  |  |  |  |
Performance Shares |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Nonvested award, cost not yet recognized, period for recognition |  |  |  |  |  |  | 2 years 1 month 13 days |  |  |  |
Granted (in shares) |  |  |  |  |  |  | 36,647 |  |  |  |
Granted, weighted average grant date fair value (in dollars per share) |  |  |  |  |  |  | $ 13.00 | $ 15.72 |  |  |
Vesting period |  |  |  |  |  |  | 3 years |  |  |  |
Options, vested in period, fair value |  |  |  |  |  |  | $ 600,000 | $ 400,000 |  |  |
Equity instruments other options, grants in period (in shares) |  |  |  |  |  |  | 64,711 |  |  |  |
Nonvested award, option, cost not yet recognized, amount |  |  |  |  |  |  | $ 200,000 |  |  |  |
Weighted average price, common shares (in dollars per share) |  |  |  |  |  |  | $ 13.21 |  |  |  |
Performance Shares | Minimum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  |  |  |  | 0.00% |  |  |  |
Performance Shares | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  |  |  |  | 150.00% |  |  |  |
2011 Plan | Stock Options |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Compensation expense |  |  | $ 100,000 | $ 600,000 |  |  |  |  |  |  |
Award vesting rights, percentage |  |  | 33.00% | 33.00% |  |  |  |  |  |  |
Granted (in shares) |  |  | 20,000 | 123,500 |  |  |  |  |  |  |
Granted (in dollars per share) |  |  | $ 7.33 | $ 12.995 |  |  |  |  |  |  |
Grants in the period, weighted average grant date fair value (in dollars per share) |  |  | $ 2.59 | $ 4.53 |  |  |  |  |  |  |
Risk free interest rate |  |  | 0.64% | 1.66% |  |  |  |  |  |  |
Expected life |  |  | 10 years | 10 years |  |  |  |  |  |  |
Expected volatility rate |  |  | 38.70% | 35.10% |  |  |  |  |  |  |
Expected dividend yield |  |  | 1.89% | 1.79% |  |  |  |  |  |  |
Nonvested award, cost not yet recognized, period for recognition |  |  | 36 months | 36 months |  |  |  |  |  |  |
2011 Plan | Stock Options | Minimum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  |  |  |  | 20.00% |  |  |  |
2011 Plan | Stock Options | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  |  |  |  | 33.00% |  |  |  |
2011 Plan | Stock Awards |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Period after grant date, awards vesting begins |  |  | 1 year | 1 year |  |  |  |  |  |  |
2005 Stock Awards Plan | Stock Awards |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Nonvested award, cost not yet recognized, period for recognition |  |  |  |  |  |  | 2 years 9 months 10 days |  |  |  |
Share-based compensation expense |  |  |  |  |  |  | $ 1,000,000.0 | $ 1,400,000 |  |  |
Total unrecognized compensation cost |  |  |  |  |  |  | $ 500,000 |  |  |  |
2005 Stock Awards Plan | Stock Awards | Minimum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  |  |  |  | 20.00% |  |  |  |
2005 Stock Awards Plan | Stock Awards | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  |  |  |  | 33.00% |  |  |  |
2015 Stock Awards Plan | Stock Awards |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares authorized (in shares) |  |  |  |  |  |  |  |  |  | 500,000 | 250,000
Award vesting rights, percentage |  |  |  |  |  |  | 20.00% |  |  |  |
Expiration period for awards |  |  |  |  |  |  | 10 years |  |  |  |
Period after grant date, awards vesting begins |  |  |  | 1 year |  | 1 year | 1 year |  |  |  |
Granted (in shares) |  | 50,000 |  | 45,418 |  | 44,949 |  |  |  |  |
Granted, weighted average grant date fair value (in dollars per share) |  | $ 5.65 |  | $ 13.00 |  | $ 15.72 |  |  |  |  |
2015 Stock Awards Plan | Stock Awards | Minimum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  | 20.00% |  | 20.00% |  |  |  |  |
2015 Stock Awards Plan | Stock Awards | Maximum |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Award vesting rights, percentage |  |  |  | 33.00% |  | 33.00% |  |  |  |  |
2015 Stock Awards Plan | Performance Shares |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  | 90,000 |  |  |  |  |  |  |  |  |
2015 Stock Awards Plan | Performance Shares | Share-based Payment Arrangement, Tranche One |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Equity instruments other options, grants in period (in shares) |  | 50,000 |  |  |  |  |  |  |  |  |
Weighted average price, common shares (in dollars per share) |  | $ 8 |  |  |  |  |  |  |  |  |
2015 Stock Awards Plan | Performance Shares | Share-based Payment Arrangement, Tranche Two |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Equity instruments other options, grants in period (in shares) |  | 40,000 |  |  |  |  |  |  |  |  |
Weighted average price, common shares (in dollars per share) |  | $ 11 |  |  |  |  |  |  |  |  |
Non Employee Director |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Issuance of shares of common stock from the treasury (in shares) | 43,063 |  |  |  | 15,909 |  |  |  |  |  |
Annual cash retainer fees | $ 345,000 |  |  |  | $ 304,000 |  |  |  |  |  |
Restricted Stock | Non Employee Director |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |
Maximum annual retainer percent |  |  |  |  |  |  | 100.00% |  |  |  |

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- Definition 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). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. + 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 (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + 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 (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + 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 (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + 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 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. + 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 (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. + 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 (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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