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Stock-based Compensation - Narrative (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Stock-based compensation | $ 1,136,000 | $ 3,155,000 | $ 3,836,000
Expected cost on shares expected to vest | $ 2,995,000 |  |
Recognition period for compensation expense not yet recognized | 3 years 2 months 12 days |  |
Weighted average shares granted (usd per share) | $ 16.72 | $ 18.63 | $ 27.05
Fully Vested and Restricted Stock | Director |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Stock-based compensation | $ 576,000 | $ 526,000 | $ 880,000
Granted (shares) | 50,316 | 21,532 | 24,427
Weighted average shares granted (usd per share) | $ 12.79 | $ 24.38 | $ 23.64
Deferred Stock Units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Granted (shares) | 12,058 | 12,304 | 14,914
Restricted Stock |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Granted (shares) | 104,789 | 62,125 | 62,320
Restricted Stock | Vesting period one |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Vesting period | 4 years |  |
Restricted Stock | Vesting period two |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Vesting period | 3 years |  |
Performance Stock Units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Vesting period | 3 years |  |
Granted (shares) | 105,857 | 89,092 | 65,421
Restricted Stock And Performance Shares |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Stock-based compensation | $ 557,000 | $ 2,630,000 | $ 2,956,000
Omnibus Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Stock-based compensation | $ 0 | $ 0 |
Share-based compensation, number of shares authorized (shares) | 2,058,000 |  |
Shares granted in period (shares) | 0 | 0 | 0
Omnibus Plan | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Vesting period | 10 years |  |
Omnibus Plan | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |
Vesting period | 1 year |  |

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- Definition Amount of cost not yet recognized for nonvested award under share-based payment 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents 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 (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount of noncash expense for share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + 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=120381028&loc=d3e5070-113901 + Details
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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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