Accumulated service period for voluntary termination.

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Date on which first half of any additional shares earned that will vest based on continued service.

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Date on which operating and balance sheet metrics are achieved.

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Date on which second half of any additional shares earned that will vest based on continued service.

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

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Percentage of additional shares to be earned subject to basic award.

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Period during which operating and balance sheet metrics are achieved.

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Share-based compensation arrangement by share-based payment award, performance period.

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

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Voluntary termination of employment age limit.

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Voluntary termination of employment terms.

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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.

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

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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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Unrecognized cost of unvested share-based compensation awards.

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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.

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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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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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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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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.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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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Share Based Compensation (Textual) (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended		12 Months Ended
	Feb. 21, 2019	Feb. 01, 2019	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Jan. 22, 2019
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			626,649		466,439
Unrecognized compensation expenses			$ 3.4
Weighted average period over which options will be recognized			1 year 8 months 12 days
Stock-based compensation expense			$ 1.6	$ 1.5
Stock-based compensation expense, capitalized			$ 0.2	0.3
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			two to three years from the initial grant dates
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			196,667
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]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	196,667
Number of restricted share right will get settled for common share	1
Voluntary Termination of Employment Age Limit	57 years
Restricted Share Rights Awards [Member] \| Certain Senior Executives [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
Period during which operating and balance sheet metrics are achieved			3 years
Date on which operating and balance sheet metrics are achieved			Dec. 31, 2021
Date on which first half of any additional shares earned that will vest based on continued service			Jan. 01, 2022
Date on which second half of any additional shares earned that will vest based on continued service			Jan. 01, 2023
Intrinsic value			$ 3.7
Weighted average grant date fair value			$ 15.61
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] \| Minimum [Member] \| Executive Officer [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 Share Rights Awards [Member] \| Maximum [Member] \| Executive Officer [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	3 years
Restricted Share Rights Awards [Member] \| Maximum [Member] \| Certain Senior Executives [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of additional shares to be earned subject to basic award			200.00%
Outperformance Feature Shares [Member] \| Maximum [Member] \| Certain Senior Executives [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			233,890
Restricted Performance Share Units Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period					3 years
Unrecognized compensation expenses			$ 4.0
Weighted average period over which options will be recognized			2 years 1 month 6 days
Stock-based compensation expense			$ 2.7	2.6
Stock-based compensation expense, capitalized			$ 0.4	$ 0.5
Common shares issued for share based compensation		147,111
Dividends Payable, Amount Per Share						$ 0.19
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			571,883		375,550
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period			213,728
Performance period			3 years