Segment Information - Summary of Company's Performance and Making Key Decision Regarding Resource Allocation (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2026 |
Mar. 31, 2025 |
Sep. 30, 2025 |
May 22, 2025 |
|
| Segment Reporting Information [Line Items] | ||||||
| Cash | $ 88,640 | $ 88,640 | $ 361,105 | |||
| Cash and marketable securities held in trust account | 239,035,116 | 239,035,116 | 234,628,166 | $ 231,150,000 | ||
| General administrative costs | 973,748 | $ 706 | 3,879,397 | $ 46,490 | ||
| Interest earned on cash and marketable securities held in trust account | 2,105,061 | 0 | 4,406,950 | 0 | ||
| Other operating segment [Member] | ||||||
| Segment Reporting Information [Line Items] | ||||||
| Cash | 88,640 | 88,640 | 361,105 | |||
| Cash and marketable securities held in trust account | 239,035,116 | 239,035,116 | $ 234,628,166 | |||
| General administrative costs | 973,748 | 706 | 3,879,397 | 46,490 | ||
| Interest earned on cash and marketable securities held in trust account | $ 2,105,061 | $ 0 | $ 4,406,950 | $ 0 | ||