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Equity Compensation (Narrative) (Details) - USD ($) $ in Thousands | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018
Equity Compensation [Abstract] |  |
Maximum shares of common stock | 20,000,000 |
Maximum annual shares awarded to employee | 500,000 |
Shares available for granting additional awards | 6,779,440 |
Unrecognized compensation cost of non-vested equity compensation awards | $ 10,600 |
Unrecognized compensation cost of non-vested equity compensation awards expected to be recognized over a weighted average period (years) | 1 year 9 months 18 days |
Number of options granted | 0 | 0
Intrinsic value of stock options exercised | $ 136 | $ 484
Stock Options |  |
Equity Compensation [Abstract] |  |
Maximum period for exercisable options (years and days) | 10 years 1 day |
Stock Options | Minimum |  |
Equity Compensation [Abstract] |  |
Vesting period (months) | 24 months |
Stock Options | Maximum |  |
Equity Compensation [Abstract] |  |
Vesting period (months) | 72 months |
Restricted Stock |  |
Equity Compensation [Abstract] |  |
Fair value of awards vested | $ 1,800 | 800
Restricted Stock | Minimum |  |
Equity Compensation [Abstract] |  |
Vesting period (months) | 12 months |
Restricted Stock | Maximum |  |
Equity Compensation [Abstract] |  |
Vesting period (months) | 60 months |
Performance Shares |  |
Equity Compensation [Abstract] |  |
Fair value of awards vested | $ 1,200 | $ 1,300
Performance Shares | Minimum |  |
Equity Compensation [Abstract] |  |
Vesting period (months) | 12 months |
Performance Shares | Maximum |  |
Equity Compensation [Abstract] |  |
Vesting period (months) | 60 months |

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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=116856206&loc=d3e5070-113901 + 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=116856206&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Number of shares authorized for issuance 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 (a)(3) -URI http://asc.fasb.org/extlink&oid=116856206&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=116856206&loc=d3e5070-113901 + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The period of time, measured from grant date, before which an equity-based award expires as specified in the award agreement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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