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

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Stock Based Compensation (Details Textual) - 2017 Incentive Plan - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares vested	115,032
Number of shares vested, weighted average fair value	$ 11.71
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum shares available under equity incentive plan				800,000
Number of shares available for grant	396,315
Stock based compensation expense	$ 1.4	$ 1.4	$ 1.7
Unrecognized compensation expense	$ 1.2
Compensation cost not yet recognized, period for recognition	2 years 2 months 12 days
Time Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share awards granted under equity incentive plan	29,045
Number of shares vested	35,006
Number of shares vested, weighted average fair value	$ 14.50
Performance Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share awards granted under equity incentive plan	50,187
Number of shares vested	80,026
Number of shares vested, weighted average fair value	$ 13.55