Fair Value Measurements - Schedule of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Sep. 30, 2025	Dec. 31, 2024
Carrying Value
Financial assets:
Promissory note receivable from Founders	$ 29,329	$ 24,369	$ 16,317
Investments in unconsolidated affiliates	25,717	18,123	13,555
Carrying Value | 2025 Convertible Notes
Financial liabilities:
Debt instruments, fair value			103,205
Carrying Value | 2029 Convertible Notes
Financial liabilities:
Debt instruments, fair value	225,523	225,258	224,505
Carrying Value | 2032 Senior Notes
Financial liabilities:
Debt instruments, fair value	293,032	292,818
Estimated Fair Value
Financial assets:
Promissory note receivable from Founders	29,329	24,369	16,317
Investments in unconsolidated affiliates	71,388	59,729	43,328
Estimated Fair Value | 2025 Convertible Notes
Financial liabilities:
Debt instruments, fair value			102,339
Estimated Fair Value | 2029 Convertible Notes
Financial liabilities:
Debt instruments, fair value	459,689	422,931	289,887
Estimated Fair Value | 2032 Senior Notes
Financial liabilities:
Debt instruments, fair value	319,404	320,734
Estimated Fair Value | Level 1
Financial assets:
Promissory note receivable from Founders	0	0	0
Investments in unconsolidated affiliates	70,203	58,573	42,478
Estimated Fair Value | Level 1 | 2025 Convertible Notes
Financial liabilities:
Debt instruments, fair value			0
Estimated Fair Value | Level 1 | 2029 Convertible Notes
Financial liabilities:
Debt instruments, fair value	0	0	0
Estimated Fair Value | Level 1 | 2032 Senior Notes
Financial liabilities:
Debt instruments, fair value	0	0
Estimated Fair Value | Level 2
Financial assets:
Promissory note receivable from Founders	0	0	0
Investments in unconsolidated affiliates	0	0	0
Estimated Fair Value | Level 2 | 2025 Convertible Notes
Financial liabilities:
Debt instruments, fair value			102,339
Estimated Fair Value | Level 2 | 2029 Convertible Notes
Financial liabilities:
Debt instruments, fair value	459,689	422,931	289,887
Estimated Fair Value | Level 2 | 2032 Senior Notes
Financial liabilities:
Debt instruments, fair value	319,404	320,734
Estimated Fair Value | Level 3
Financial assets:
Promissory note receivable from Founders	29,329	24,369	16,317
Investments in unconsolidated affiliates	1,185	1,156	850
Estimated Fair Value | Level 3 | 2025 Convertible Notes
Financial liabilities:
Debt instruments, fair value			0
Estimated Fair Value | Level 3 | 2029 Convertible Notes
Financial liabilities:
Debt instruments, fair value	0	0	$ 0
Estimated Fair Value | Level 3 | 2032 Senior Notes
Financial liabilities:
Debt instruments, fair value	$ 0	$ 0