Significant Accounting Policies - Net Income (Loss) Per Share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Schedule of reconciliation of shares used to calculate basic and diluted earnings per share
Weighted average shares outstanding used to compute basic earnings per share (in shares)	23,948	23,004	23,966	22,193
Incremental shares issuable upon the assumed exercise of stock options (in shares)	4	12	5	16
Unvested restricted stock and restricted stock units (in shares)	161	198	160	223
Shares used to compute diluted earnings per share (in shares)	24,113	23,214	24,131	22,432
Anti-dilutive shares excluded from the diluted earnings per share calculation (in shares)	377	123	293	42