Related Party Transactions - Related Party Transactions (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Sep. 30, 2023	Dec. 31, 2025	Dec. 31, 2023
Related Party Transaction [Line Items]
Capitalized stock-based compensation	$ 316	$ 157
Affiliated Entity | Ursa Space Systems
Related Party Transaction [Line Items]
Total payments	83	125
Investor | Seahawk
Related Party Transaction [Line Items]
Total payments	0	0
Amount of debt extinguishment			$ 18,400
Other liabilities	0			$ 0
Investor | Intelsat
Related Party Transaction [Line Items]
Total payments		220
Debt instrument, face amount					$ 50,000
Investor | Common stock warrants (exercisable for Class A common stock) treated as equity | Seahawk
Related Party Transaction [Line Items]
Warrants issued (in shares)			13.5
Investor | Common stock warrants (exercisable for Class A common stock) treated as equity | Intelsat
Related Party Transaction [Line Items]
Warrants issued (in shares)			20.2
Equity Method Investee | Ursa Space Systems
Related Party Transaction [Line Items]
Other liabilities	42			0
Equity Method Investee | Thales Alenia Space
Related Party Transaction [Line Items]
Total payments	2,556	$ 0
Other liabilities	$ 92			$ 0