Stockholders' Equity and Stock Repurchase Program (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2015	Oct. 27, 2014
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred stock, shares issued (in shares)	883,000	883,000
Cumulative annual dividend rate (as a percent)	5.00%	5.00%
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares outstanding (in shares)	883,000	883,000
Preferred stock, value	$ 3,532,000	$ 3,532,000
Liquidation preference over common stock (in dollars per share)	$ 4	$ 4
Stock repurchase program, authorized amount					$ 5,000,000.0
Shares repurchased (in shares)	0	0	0	908,000
Average price of shares repurchased (in dollars per share)				$ 2.52
Total purchase price				$ 2,300,000
Stock repurchase program remaining authorized repurchase amount	$ 2,700,000
Preferred stock dividends payable	$ 2,901,000	$ 2,901,000
Series A Preferred Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred stock, shares issued (in shares)	883,000	883,000
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares outstanding (in shares)	883,000	883,000
Preferred stock dividends payable				$ 2,900,000