Share-Based Compensation and Other Compensation Matters (Details 5) - Deferred Share Award [Member] - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Number of Deferred Share Awards Granted (in shares or units) | 10,032 | 24,944 | 24,056 |
| Aggregate Grant Date Fair Value | $ 326 | $ 671 | $ 642 |
| Grant Date Fair Value Per Share (in dollars per share) | $ 32.47 | $ 26.89 | $ 26.70 |
| Number of common shares issued (in shares) | 15,590 | 12,028 | 15,485 |
| Grant date fair value (in dollars per share) | $ 26.89 | $ 26.70 | $ 26.77 |
| Aggregate intrinsic value | $ 508 | $ 322 | $ 413 |
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- Definition The aggregate 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). No definition available.
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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). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Definition Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options. No definition available.
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- Details
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