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		6 Months Ended		12 Months Ended
Share Based Compensation (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 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	$ 10,270		$ 10,270
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	195,984		195,984		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			0
Share-based Payment Arrangement, Expense	$ 1,200	$ 900	$ 2,500	$ 2,000
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	2,590		$ 2,590
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	4,071		4,071
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	2,402		2,402
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	1,043		1,043
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	$ 164		$ 164
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	615,333		615,333
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	61,317		61,317
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