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Share-Based Compensation - Narrative (Details) - USD ($)		1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 16, 2026	May 31, 2026	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Jul. 02, 2026	Jul. 01, 2026	Dec. 31, 2025	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total compensation cost			$ 10,275,587	$ 790,657	$ 13,933,089	$ 966,359
Options, outstanding (in shares)			12,264,306	6,534,000	12,264,306	6,534,000			6,459,000	0
Options, outstanding (in dollars per share)			$ 0.60	$ 0.21	$ 0.60	$ 0.21			$ 0.21	$ 0
Property, Plant and Equipment
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total compensation cost			$ 200,000	$ 0	$ 200,000	$ 0
Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in dollars per share)					$ 10.04	$ 0.97
Equity instruments other than options, nonvested (in shares)			12,731,588	5,585,000	12,731,588	5,585,000			5,585,000	0
Equity instruments other than options, nonvested (in dollars per share)			$ 8.11	$ 0.97	$ 8.11	$ 0.97			$ 0.76	$ 0
Restricted Stock \| Officer
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Equity instruments other than options, nonvested (in shares)			3,577,100		3,577,100
Restricted Stock Units (RSUs)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Granted (in dollars per share)	$ 15.00
Restricted Stock Units (RSUs) \| Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Award vesting period	1 year
Restricted Stock Units (RSUs) \| Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Award vesting period	3 years
2025 Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Award vesting period					4 years
2025 Plan \| Officer \| Common Class B
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Options, outstanding (in shares)		305,790
Options, outstanding (in dollars per share)		$ 1.635
2025 Plan \| Restricted Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Award vesting period		4 years
2025 Plan \| Restricted Stock \| Officer \| Common Class B
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Equity instruments other than options, nonvested (in shares)		941,222
Equity instruments other than options, nonvested (in dollars per share)		$ 1.635
2025 Plan \| Stock options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Award vesting period		4 years
2026 Equity Incentive Plan \| Common Class A
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares reserved for future issuance (in shares)								18,125,474
2026 Equity Incentive Plan \| Awards Granted in Connection with IPO \| Common Class A
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares reserved for future issuance (in shares)								9,134,602
2026 ESPP \| Employee Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares reserved for future issuance (in shares)							5,437,642
Share-based payment award, shares issued in period (in shares)					0