Represents the number of units accrued under dividend equivalents.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that are scheduled to vest.

+ References

No definition available.

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- Definition

Number of vested equity instruments other than options outstanding.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Publisher FASB
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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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
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-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 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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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)
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
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Deferred Compensation Agreements and Stock-Based Compensation - Restricted Stock Units (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended			56 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017
Weighted Average Grant Date Fair Value per Unit
Accrued dividend equivalent units	3,097			3,097
Restricted Stock Units
Units
Granted, Units				259,065
Weighted Average Grant Date Fair Value per Unit
Number of Units to Vest	85,415			85,415
Restricted Stock Units \| 2018
Weighted Average Grant Date Fair Value per Unit
Number of Units to Vest	28,471			28,471
Restricted Stock Units \| 2019
Weighted Average Grant Date Fair Value per Unit
Number of Units to Vest	51,552			51,552
Restricted Stock Units \| 2020
Weighted Average Grant Date Fair Value per Unit
Number of Units to Vest	5,392			5,392
Equity Plan \| Restricted Stock Units
Units
Beginning Balance, Units	149,809
Granted, Units	10,000	100,553	0	259,065
Vested, Units	(74,394)
Ending Balance, Units	85,415	149,809		85,415
Weighted Average Grant Date Fair Value per Unit
Beginning Balance, Weighted Average Grant Date Fair Value per Unit	$ 24.70
Granted, Weighted Average Grant Date Fair Value per Unit	22.90	$ 23.87
Vested, Weighted Average Grant Date Fair Value per Unit	25.53
Ending Balance, Weighted Average Grant Date Fair Value per Unit	$ 23.76	$ 24.70		$ 23.76
Total fair value of Units vested	$ 1,700	$ 600	$ 900
Number of vested units	173,650			173,650
Compensation expense recognized	$ 1,100	$ 1,600	$ 1,100
Unrecognized compensation expense	$ 1,200			$ 1,200
Period to recognize unrecognized compensation expense	1 year 7 months 6 days
Accrued dividend equivalent units	3,097			3,097
Executives \| Equity Plan \| Restricted Stock Units
Units
Granted, Units				259,065