Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		26 Months Ended
	May 29, 2018	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation		$ 558	$ 1,179	$ 1,238	$ 2,034
Expected cost on shares expected to vest		$ 5,036		$ 5,036		$ 5,036
Recognition period for compensation expense not yet recognized				3 years 9 months 18 days
Restricted Stock \| Vesting Period 2
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period				3 years
Restricted Stock \| Vesting Period 2 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period						1 year
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period	3 years