Computation of Net Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2023	Sep. 30, 2022
Computation of Net Earnings per Share
Net income available to common stockholders	$ 65,931	$ 61,579	$ 47,697	$ 40,283	$ 44,189	$ 41,614	$ 175,207	$ 126,087
Weighted average shares of common stock outstanding used in computing basic income per share	32,807			33,011			32,775	33,116
Incremental options and RSUs	352			378			433	522
Weighted average shares of common stock used in computing diluted net income per share	33,159			33,389			33,208	33,638
Net income per share
Basic	$ 2.01			$ 1.22			$ 5.35	$ 3.81
Diluted	$ 1.99			$ 1.21			$ 5.28	$ 3.75
Anti-dilutive common equivalent shares excluded from calculation	734			5,046			2,598	6,692