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

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

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Share Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
Share Based Compensation (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 8,923		$ 8,923
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	194,722		194,722		152,631
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period			(27,719)	(18,800)
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			8,736	5,879
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings			18,983	12,921
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period			(1,262)
Share-based Payment Arrangement, Expense	$ 1,200	$ 1,000	$ 3,800	$ 3,100
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease)			(3,368)
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	1,287		$ 1,287
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	4,047		4,047
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	2,388		2,388
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	1,038		1,038
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	$ 163		$ 163
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	616,083		616,083
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			74,440
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	127,200		127,200
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, Equity Instruments Other than Options, Nonvested, Number	60,805		60,805
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	600,000		600,000
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	0		58,740
Performance Shares [Member] \| 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, Options, Grants in Period, Gross				48,053
Restricted Stock Units (RSUs) [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
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		13,637