Summary of Significant Accounting Policies - Warrants (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Jul. 26, 2016
Accounting Policies [Abstract]
Number of warrants outstanding (in shares)	801,246	801,370	810,811
Exercise price of warrants (in dollars per share)	$ 46.911	$ 46.911	$ 55.93
Number of securities called by each warrant (in shares)	1.15	1.15	1
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Number of securities called by outstanding warrants (in shares)	921,433	921,576
Shares issued upon exercise of warrants (in shares)	143
Shares withheld upon exercise of warrants (in shares)	17