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Stock-Based Compensation (Narrative) (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Stock-based compensation | $ 1,696,000 | $ 1,346,000 | $ 1,471,000 |
Share based compensation cost not recognized | $ 3,687,000 |  |  |
Period in which compensation will be recognized | 3 years 3 months |  |  |
Excess income tax deficiency from share-based compensation | $ 0 | $ (332,000) | $ 253,000 |
Income tax expense, excess tax benefits | $ 127,000 |  |  |
Granted, weighted average grant price (usd per share) | $ 14.46 | $ 12.50 | $ 44.93 |
Equity Option |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Stock options granted, shares |  |  | 0 |
Restricted Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Shares granted other than options, shares | 175,196 | 48,283 | 29,656 |
Share-based units, shares | 186,806 | 79,272 | 93,817 | 108,237
Deferred Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Shares granted other than options, shares | 26,860 | 0 | 0 |
Share-based units, shares | 26,860 | 0 | 0 | 0
Share based awards, vesting period | 3 years |  |  |
Performance Stock Units |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Stock-based compensation | $ 1,499,000 | $ 648,000 | $ 937,000 |
Shares granted other than options, shares | 120,583 | 129,844 | 41,114 |
Share-based units, shares | 181,341 | 63,690 | 35,999 | 71,990
Non-Employee Directors | Fully-Vested Stock Awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Stock-based compensation | $ 704,000 | $ 698,000 | $ 534,000 |
Shares granted other than options, shares | 39,280 | 59,598 | 14,000 |
Granted, weighted average grant price (usd per share) | $ 17.92 | $ 11.72 | $ 38.15 |
The Omnibus Plan |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Stock-based compensation | $ 0 | $ 0 | $ 0 |
Share-based compensation, number of shares authorized | 1,270,000 |  |  |
Stock options granted, shares | 0 | 0 | 0 |
March 2015 | Restricted Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |
Share based awards, vesting period | 3 years |  |  |

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- Definition Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount + References No definition available. + Details
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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 Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 20 -Section 55 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=96864182&loc=d3e11374-113907 + 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 number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + 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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