Share based compensation arrangement by share based payment award measurement period commencement date.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award measurement period end date.

+ References

No definition available.

+ Details

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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

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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

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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

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Share Based Compensation - Restricted Performance Share Units (Details) - Restricted Performance Share Units Plan [Member] - Executive Officer [Member] - USD ($) $ in Thousands				3 Months Ended
	Feb. 28, 2018	Mar. 01, 2017	Feb. 22, 2016	Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2018, shares				400,488
Granted, shares				209,193
Units Cancelled				0
Non-vested at March 31, 2018, shares				609,681
Units Granted	209,193	174,854	231,388
Fair Value of Units on Grant Date (in thousands)	$ 4,276	$ 3,735	$ 3,558
February 22, 2016 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2018, shares				228,077
Granted, shares				0
Units Cancelled				0
Non-vested at March 31, 2018, shares				228,077
Measurement Period Commencement Date				Jan. 01, 2016
Measurement Period End Date				Dec. 31, 2018
March 01, 2017 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2018, shares				172,411
Granted, shares				0
Units Cancelled				0
Non-vested at March 31, 2018, shares				172,411
Measurement Period Commencement Date				Jan. 01, 2017
Measurement Period End Date				Dec. 31, 2019
February 28, 2018 RSPU Grant [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2018, shares				0
Granted, shares				209,193
Units Cancelled				0
Non-vested at March 31, 2018, shares				209,193
Measurement Period Commencement Date				Jan. 01, 2018
Measurement Period End Date				Dec. 31, 2020