Stockholders' Equity - Warrants (Details) - $ / shares	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2021
Warrants
Number of shares into which warrant issued during period may be converted (in shares)	129,491
Warrant exercise price per share (in dollars per share)	$ 0.05
Contractual life of warrants	10 years
Number of shares of common stock into which warrants may be converted (in shares)		39,474