Stockholders' Equity - Per Share Results (Details) - USD ($) $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2021	Dec. 31, 2020
Earnings per share:
Net income (loss)	$ 1,981	$ (255)	$ 14,144	$ (10,481)
Weighted average shares outstanding - basic	5,663,000	5,075,000	7,908,000	5,309,000
Incremental shares from assumed exercise of Griffin stock options	181,000		173,000
Adjusted weighted average shares for computation of diluted per share results	5,844,000	5,075,000	8,081,000	5,309,000
Incremental shares from assumed exercise of stock options excluded due to anti-dilutive effect			68,000