Accumulated service period for voluntary termination.

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- Definition

Number of restricted share right will get settled for number of common share.

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No definition available.

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- Definition

Number of vesting installments.

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No definition available.

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- Definition

Share-based compensation arrangement by share-based payment award vesting date.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award vesting period1.

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- Definition

Voluntary termination of employment age limit.

+ References

No definition available.

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- Definition

Voluntary termination of employment terms.

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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
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(ii)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
-Subparagraph (i)
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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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)(1)
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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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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).

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

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

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- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Share Based Compensation (Textual) (Details) $ / shares in Units, $ in Millions			3 Months Ended
	Feb. 28, 2018 Installment shares	Feb. 01, 2018 shares	Mar. 31, 2018 USD ($) shares	Mar. 31, 2017 USD ($)	Feb. 09, 2018 $ / shares	Dec. 31, 2017 shares
Restricted Share Rights Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			632,665			455,643
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			two to three years from the initial grant dates
Unrecognized compensation expenses \| $			$ 3.3
Weighted average period over which options will be recognized			1 year 7 months 6 days
Share-based compensation expense, capitalized \| $			$ 0.3	$ 0.3
Share-based compensation expense \| $			$ 1.5	1.5
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			178,549
Voluntary Termination Of Employment Terms			after reaching at least age 57 and accumulating at least 15 years of service with the Company
Accumulated Service Period For Voluntary Termination			15 years
Restricted Share Rights Awards [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Voluntary Termination of Employment Age Limit			57 years
Restricted Share Rights Awards [Member] \| Non-Officer Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	44,062
Number of restricted share right will get settled for common share	1
Number of Vesting Installments \| Installment	3
Restricted Share Rights Awards [Member] \| Cliff Vest [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	134,487
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date	Apr. 15, 2021
Restricted Share Rights Awards [Member] \| Installment One [Member] \| Non-Officer Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date	Apr. 15, 2019
Restricted Share Rights Awards [Member] \| Installment Two [Member] \| Non-Officer Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date	Apr. 15, 2020
Restricted Share Rights Awards [Member] \| Installment Three [Member] \| Non-Officer Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share Based Compensation Arrangement By Share Based Payment Award, Vesting Date	Apr. 15, 2021
Restricted Share Rights Awards [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			2 years
Restricted Share Rights Awards [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
Restricted Performance Share Units Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			three-year
Unrecognized compensation expenses \| $			$ 3.5
Weighted average period over which options will be recognized			1 year 9 months 18 days
Share-based compensation expense, capitalized \| $			$ 0.5	0.5
Share-based compensation expense \| $			$ 2.6	$ 2.4
Common shares issued for share based compensation		193,516
Dividends Payable, Amount Per Share \| $ / shares					$ 0.18
Restricted Performance Share Units Plan [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number			609,681			400,488
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			209,193
Restricted Performance Share Units Plan [Member] \| Cliff Vest [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights			three year cliff vesting period