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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- Definition

Number of vesting installments.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Issuance, Percentage

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- Definition

Vesting Acceleration Period

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- Definition

Voluntary Termination Of Employment Age Limit

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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Amount of cost capitalized for award under share-based payment arrangement.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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- 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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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.

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Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

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No definition available.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

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Share Based Compensation - Narrative (Details) $ / shares in Units, $ in Millions				3 Months Ended
	Mar. 05, 2020 USD ($) installment $ / shares shares	Feb. 01, 2020 shares	Mar. 01, 2017	Mar. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2019 USD ($)	Jan. 22, 2020 $ / shares	Dec. 31, 2019 $ / shares shares
Restricted Share Rights Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expenses \| $				$ 3.5
Weighted average period over which options will be recognized				1 year 4 months 24 days
Share-based compensation expense \| $				$ 1.9	$ 1.6
Share-based compensation expense, capitalized \| $				$ 0.3	0.2
Granted (in shares)				224,678
Restricted share rights outstanding (in shares)				689,184			479,144
Weighted average grant date fair value (in dollars per shares) \| $ / shares				$ 15.50			$ 15.90
Restricted Share Rights Awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				1 year
Restricted Share Rights Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Restricted Performance Share Units Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years	3 years
Unrecognized compensation expenses \| $				$ 6.9
Weighted average period over which options will be recognized				2 years 4 months 13 days
Share-based compensation expense \| $				$ 0.6	2.7
Share-based compensation expense, capitalized \| $				$ 0.1	$ 0.4
Common shares issued for share based compensation (in shares)		121,897
Dividends payable (in dollars per share) \| $ / shares						$ 0.19
Executive Officer \| Restricted Share Rights Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	183,758
Number of restricted share right will get settled for common share (in shares)	1
Voluntary termination of employment age limit	57
Accumulated service period for voluntary termination	15 years
Performance earning potential	200.00%
Restricted share rights outstanding (in shares)	316,306
Intrinsic value of awards \| $	$ 4.6
Weighted average grant date fair value (in dollars per shares) \| $ / shares	$ 14.66
Executive Officer \| Restricted Share Rights Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Executive Officer \| Restricted Performance Share Units Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				319,600
Restricted share rights outstanding (in shares)				715,965			396,365
Non Officer Employees \| Restricted Share Rights Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	40,920
Number of vesting installments \| installment	3
Vesting acceleration period	1 year