Represents the number of trustees in equity compensation plan.

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- Definition

Represents the market value of shares, newly issued during the reporting period under the plan, to each individual.

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- Definition

Represents the number of non-vested shares that are scheduled to vest in year four.

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Represents the number of non-vested shares that are scheduled to vest in year one.

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- Definition

Represents the number of non-vested shares that are scheduled to vest in year three.

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No definition available.

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Represents the number of non-vested shares that are scheduled to vest in year two.

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- Definition

Represents the aggregate market value at grant date for nonvested equity-based awards during the period on other than stock (or unit) options plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

No definition available.

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- Definition

Share-based Compensation Awards, Number of Installments

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No definition available.

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

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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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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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No definition available.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of new stock issued during the period.

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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Shareholders' Equity - Share Awards (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) installment trustee shares	Dec. 31, 2018 USD ($) trustee shares	Dec. 31, 2017 USD ($) trustee shares	Dec. 31, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of shares, net \| $		$ 639,783	$ 493,866
Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of shares, net (in shares)		23,281,738	6,976,757
Issuance of shares, net \| $		$ 233	$ 70
Officers and Other Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of shares, net (in shares)	103,100	14,675	14,337
Issuance of shares, net \| $	$ 3,080	$ 995	$ 1,067
2009 Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	136,100	19,925	18,837
Number of installments \| installment	5
Unvested shares (in shares)	106,680	55,321	26,062	24,743
2020 (in shares)	32,677
2021 (in shares)	28,875
2022 (in shares)	24,808
2023 (in shares)	20,320
Estimated future compensation expense for the unvested shares \| $	$ 3,672
Weighted average period of recognition of compensation expenses (in years)	25 months
Compensation expense \| $	$ 3,088	$ 1,337	$ 1,377
Shares available for issuance under plan (in shares)	211,334
2009 Award Plan \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	3,000
Aggregate market value of shares awarded \| $	$ 270
Market value of common shares awarded to each trustee (in dollars) \| $	$ 90
2009 Award Plan \| Trustees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of trustees \| trustee	8	6	6
Shares granted (in shares)	3,000	750	750
Aggregate market value of shares awarded \| $	$ 575	$ 254	$ 392
Market value of common shares awarded to each trustee (in dollars) \| $	$ 72	$ 42	$ 65
2009 Award Plan \| Managing Trustee \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of trustees \| trustee	3
Shares granted (in shares)	750
Aggregate market value of shares awarded \| $	$ 41