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Stockholders' Equity - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	May 31, 2026	Apr. 30, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock acquired	$ 403.8	$ 187.7	$ 1,009.4	$ 187.7
Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares repurchased (in shares)	4.6	2.4	13.2	2.4
Common stock withheld related to net share settlement of equity awards (in shares)	0.1		0.6
2025 Share Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount							$ 750.0
Shares repurchased (in shares)					7.7
Shares of common stock acquired					$ 500.0
Stock repurchase program, remaining amount						$ 250.0
2026 Share Repurchase Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount						$ 1,000.0
Shares repurchased (in shares)	4.6		13.2
Shares of common stock acquired	$ 400.0		$ 1,000.0
RSUs and PSUs \| Equity Incentive Plan 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized estimated compensation costs	$ 219.4		$ 219.4
Unrecognized compensation costs recognized weighted average period (in years)			1 year 10 months 24 days