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

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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, 401(k) Plan and Deferred Compensation - Restricted Performance Share Units (Details) - USD ($) $ in Thousands				12 Months Ended
	Mar. 01, 2017	Feb. 22, 2016	Feb. 23, 2015	Dec. 31, 2017	May 18, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units Granted					6,500,000
Restricted Performance Share Units Plan [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2017, shares				378,977
Granted, shares				174,854
Units Cancelled				(8,028)
Non-vested at December 31, 2017, shares				545,803
Units Granted	174,854	231,388	186,395
Fair Value of Units on Grant Date (in thousands)	$ 3,735	$ 3,558	$ 3,933
Restricted Performance Share Units Plan [Member] \| February 23, 2015 RSPU Grant [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2017, shares				147,589
Granted, shares				0
Units Cancelled				(2,274)
Non-vested at December 31, 2017, shares				145,315
Measurement Period Commencement Date				Jan. 01, 2015
Measurement Period End Date				Dec. 31, 2017
Restricted Performance Share Units Plan [Member] \| February 22, 2016 RSPU Grant [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2017, shares				231,388
Granted, shares				0
Units Cancelled				(3,311)
Non-vested at December 31, 2017, shares				228,077
Measurement Period Commencement Date				Jan. 01, 2016
Measurement Period End Date				Dec. 31, 2018
Restricted Performance Share Units Plan [Member] \| March 01, 2017 RSPU Grant [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-vested at January 1, 2017, shares				0
Granted, shares				174,854
Units Cancelled				(2,443)
Non-vested at December 31, 2017, shares				172,411
Measurement Period Commencement Date				Jan. 01, 2017
Measurement Period End Date				Dec. 31, 2019