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

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Number of shares authorized for issuance under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Share Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended					9 Months Ended
Share Based Compensation (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
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	204,108					204,108		194,722
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(6,205)	(1,500)	(36,674)		(27,719)	(44,379)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period						(3,101)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease)						(5,399)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation	1,860	530	11,646		8,736
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings	4,345	970	25,028		18,983
Share-based Payment Arrangement, Expense	$ 1,200			$ 1,200		$ 3,700	$ 3,800
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 8,401					$ 8,401
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number	174,087					174,087
Expense to be paid next twelve months [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 1,198					$ 1,198
Expense to be paid Year Two [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	3,644					3,644
Expense to be paid Year Three [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	2,401					2,401
Expense to be paid Year Four [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	997					997
Expense to be paid Year Five [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 161					$ 161
2017 Employees Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	750,000					750,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	537,735					537,735
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						62,265
2017 Non Employee Directors LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	150,000					150,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	113,700					113,700
2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	600,000					600,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	18,695					18,695
Performance Shares [Member] \| 2017 Employees Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross						62,265	58,740
Restricted Stock Units (RSUs) [Member] \| 2017 Employees Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross							15,700