Summary of Significant Accounting Policies - Reconciliation of shares used to determine net income per share (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Summary of Significant Accounting Policies
Net income	$ 52,247	$ 103,801	$ 32,259
Weighted average number of shares - basic	45,385,433	44,990,104	43,765,443
Shares underlying options	1,952,798	2,118,914	2,875,379
Weighted average number of shares outstanding - diluted	47,338,231	47,109,018	46,640,822