Net Income Per Share - Reconciliation of EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Reconciliation of basic earnings per share ("EPS") to diluted EPS
Net income available to common stockholders	$ 103,541	$ 97,831	$ 181,425	$ 173,258
Basic weighted-average shares outstanding	41,705	42,251	41,775	42,319
Dilutive effect of potential common stock equivalents	133	167	151	215
Diluted weighted-average shares outstanding	41,838	42,418	41,926	42,534
Net income per common share:
Basic	$ 2.48	$ 2.32	$ 4.34	$ 4.09
Diluted	$ 2.47	$ 2.31	$ 4.33	$ 4.07

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

Simpson Manufacturing Co., Inc. 10-Q