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Share-Based Payments - Restricted Share Units by Grant Year (Details) - Restricted Share Units | 12 Months Ended
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Dec. 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Outstanding (in shares) | 439,576
Grants 2017 |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 200,020.707095856
Vested (in shares) | 0
Forfeited (in shares) | 19,585
Outstanding (in shares) | 180,436
Grants 2016 |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 328,550
Vested (in shares) | 104,041.666666667
Forfeited (in shares) | 40,579
Outstanding (in shares) | 183,929
Grants 2015 |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Granted (in shares) | 287,852
Vested (in shares) | 173,755
Forfeited (in shares) | 38,886
Outstanding (in shares) | 75,211

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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + 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)(1)(iv)(3) -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 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 The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + 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)(2) -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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