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Stock-Based Compensation (Narrative) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award |  |
Stock-based compensation | $ 3,836,000 | $ 1,696,000
Expected cost on shares expected to vest | $ 5,347,000 |
Recognition period for compensation expense not yet recognized | 3 years 3 months 18 days |
Weighted average shares granted (usd per share) | $ 27.05 | $ 14.46
Fully Vested and Restricted Stock | Director |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Stock-based compensation | $ 880,000 | $ 704,000
Granted (shares) | 24,427 | 39,280
Weighted average shares granted (usd per share) | $ 23.64 | $ 17.92
Deferred Stock Units |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Granted (shares) | 14,914 | 26,860
Restricted Stock |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Granted (shares) | 62,320 | 175,196
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 |  |
Granted (shares) | 65,421 | 120,583
Vesting period | 3 years |
Restricted Stock And Performance Shares |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Stock-based compensation | $ 2,956,000 | $ 1,499,000
Omnibus Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |
Stock-based compensation | $ 0 | $ 0
Share-based compensation, number of shares authorized (shares) | 1,270,000 |
Shares granted in period (shares) | 0 | 0

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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of grants made 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://www.xbrl.org/2003/role/presentationRef -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=96867065&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://www.xbrl.org/2003/role/presentationRef -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=96867065&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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