Earnings per share - Computation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Numerator
Net income	$ 93,245	$ 74,754	$ 170,068	$ 114,369
Denominator
Weighted average common shares outstanding for basic earnings per share (in shares)	127,116	131,730	127,029	133,369
Dilutive potential common stock outstanding
Weighted average common shares outstanding for diluted earnings per share (in shares)	129,222	133,543	129,097	135,758
Earnings per share
Basic (usd per share)	$ 0.73	$ 0.57	$ 1.34	$ 0.86
Diluted (usd per share)	$ 0.72	$ 0.56	$ 1.32	$ 0.84
Convertible Notes
Dilutive potential common stock outstanding
Dilutive potential common stock outstanding (in shares)	0	0	0	116
Stock options
Dilutive potential common stock outstanding
Dilutive potential common stock outstanding (in shares)	1,762	1,656	1,669	1,910
RSUs, PSUs and ESPP
Dilutive potential common stock outstanding
Dilutive potential common stock outstanding (in shares)	344	157	399	363

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