Summary of Significant Accounting Policies - Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Net Earnings per Share
Securities excluded from diluted loss per share calculation (in shares)	32,641,851	33,307,113
Options to purchase common stock
Net Earnings per Share
Securities excluded from diluted loss per share calculation (in shares)	5,814,506	6,467,956
Unvested restricted stock awards
Net Earnings per Share
Securities excluded from diluted loss per share calculation (in shares)	78,300	146,800
Unvested restricted stock units
Net Earnings per Share
Securities excluded from diluted loss per share calculation (in shares)	322,182	265,494
Warrants to purchase common stock
Net Earnings per Share
Securities excluded from diluted loss per share calculation (in shares)	26,426,863	26,426,863