Summary of Significant Accounting Policies - Net earnings per common share (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Oct. 27, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Net (loss) earnings		$ (1,865)	$ 13,190	$ 14,678	$ 9,361
Allocation to nonvested restricted stock awards			199	(213)	146
Net (loss) earnings available to common stockholders		$ (1,865)	$ 12,991	$ 14,465	$ 9,215
Weighted-average shares outstanding - basic and diluted		35,914,000	35,836,000	35,914,000	35,836,000
Net (loss) earnings per common share - basic and diluted		$ (0.05)	$ 0.36	$ 0.40	$ 0.26
Options outstanding (in shares)		0	0	0	0
Semi annual cash dividend on both classes of common stock
Semi- annual cash dividend declared	$ 0.04