Accelerated Amortization Expense

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- Definition

Accrued Amortization Expense Relating To Employee Separation

+ References

No definition available.

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- Definition

Aggregate Fair Value of Awards on Grant Date

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- Definition

Aggregate Fair Value Of Restricted Shares Granted To Employees On Grant Date

+ References

No definition available.

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- Definition

Aggregate Fair Value Of Restricted Shares Granted To Employees and Trustees On Grant Date

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No definition available.

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- Definition

Aggregate Fair Value Per Share Based On Monte Carlo Simulation

+ References

No definition available.

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- Definition

Common Stock Share Average Price On Grant Date

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No definition available.

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- Definition

Fair Value Of Non Employee Trustee Awards Granted

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No definition available.

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- Definition

Fair Value Of Restricted Share Based Employee Compensation Vested

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No definition available.

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- Definition

Number Of Days For Additional Acquisition Of Restricted Share Units

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No definition available.

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- Definition

Restricted Share Compensation Cost Weighted Average Time To Vest

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No definition available.

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- Definition

Share Based Compensation Arrangement By Time Based Payment Award Vesting Period

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No definition available.

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- Definition

Share Based Compensation Common Stock Shares Authorized For Issuance

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No definition available.

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- Definition

Share Based Compensation Restricted Share Unit Award Future Compensation Expense

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No definition available.

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- Definition

Unrecognized Compensation Expense

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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 share instruments newly issued under a share-based compensation plan.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Share Based Compensation (Narrative) (Detail) - USD ($) $ / shares in Units, $ in Thousands	10 Months Ended	12 Months Ended
	Feb. 27, 2013	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 29, 2018	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount		$ 100	$ 100	$ 200
Aggregate Fair Value Of Restricted Shares Granted To Employees and Trustees On Grant Date		$ 5,100	4,800	5,100
Weighted average period		8 months 16 days
Fair value of shares vested		$ 2,000	3,900	3,600
Number of days for acquisition of RSUs		20 days
Aggregate fair value of awards		$ 800	700			$ 800
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period		0
Unrecognized compensation expense		$ 300
Restricted Shares Awarded to Non-Employee Trustees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate compensation expense		6,900	5,700	6,000
Accrued amortization relating to employee separation		$ 100	200	300
2003 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total remaining number of common shares to be issued		1,718,352
Time Based Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate compensation expense		$ 4,300	$ 3,900	$ 3,300
Number of awards granted		392,697	245,950	230,429
Common share per share on the date of grant		$ 10.99	$ 16.43			$ 18.67
Accelerated amortization relating to employee separation		$ 100	$ 200	$ 200
Time Based Vesting [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vest over period		1 year
Time Based Vesting [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares vest over period		3 years
Employees grants only [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate Fair Value Of Restricted Shares Granted To Employees and Trustees On Grant Date		$ 4,300
Aggregate Fair Value Of Restricted Shares Granted To Employees On Grant Date			4,000	4,300
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate compensation expense		$ 2,100	$ 1,300	1,800
Number of awards granted	127,421	115,613.5	140,490
Accelerated amortization relating to employee separation			$ 400
Aggregate fair value of awards		$ 1,779	$ 1,620		$ 1,336	$ 1,914
Aggregate fair values of RSU awards per share		$ 14.56	$ 11.53		$ 10.93	$ 15.02
Future compensation expense		$ 5,600
Non Employee Trustee Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate compensation expense		500	$ 500	600
Fair value of shares granted to non-employee trustees		$ 600	$ 800	$ 800