Stockholders' Equity - Number of Shares (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Reconciliation of the number of shares outstanding with the number of shares used in computing basic and diluted earnings per share
Common shares outstanding, end of period	35,774	36,042	35,774	36,042
Effect of using weighted average common shares outstanding	79	254	192	286
Shares used in computing earnings per share-basic	35,853	36,296	35,966	36,328
Effect of shares issuable under stock option plans based on the treasury stock method	32	73	39	100
Effect of restricted and contingently issuable shares	87	65	73	72
Shares used in computing earnings per share-diluted	35,972	36,434	36,078	36,500