Stockholders' Equity - Schedule of Development Subsidiaries and Their Product Candidates (Details) - Subsidiaries [Member] |
Jun. 30, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Cullinan M I C A Corp [Member] | ||
| Common Stock And Noncontrolling Interest In Subsidiaries [Line Items] | ||
| Subsidiary, Ownership Percentage | 99.00% | 99.00% |
| Cullinan Florentine Corp [Member] | ||
| Common Stock And Noncontrolling Interest In Subsidiaries [Line Items] | ||
| Subsidiary, Ownership Percentage | 98.00% | 98.00% |
| Cullinan Amber Corp [Member] | ||
| Common Stock And Noncontrolling Interest In Subsidiaries [Line Items] | ||
| Subsidiary, Ownership Percentage | 96.00% | 96.00% |