| Reconciliation of Revenue from Segments to Consolidated [Table Text Block] |
| | | Three Months Ended June 30, | | | Six Months Ended June 30, | |
| | | 2025 | | | 2024 | | | 2025 | | | 2024 | |
| Revenues | | | | | | | | | | | | | | | | |
| Leasing | | $ | 3,571,000 | | | $ | 3,899,000 | | | $ | 6,562,000 | | | $ | 8,152,000 | |
| Direct patient services | | | 3,500,000 | | | | 3,157,000 | | | | 6,621,000 | | | | 4,120,000 | |
| Total | | $ | 7,071,000 | | | $ | 7,056,000 | | | $ | 13,183,000 | | | $ | 12,272,000 | |
|
| Segment, Reconciliation of Other Items from Segments to Consolidated [Table Text Block] |
| | | 2025 | | | 2024 | | | 2025 | | | 2024 | |
| Depreciation, amortization, and other expense | | | | | | | | | | | | | | | | |
| Leasing | | $ | 960,000 | | | $ | 1,219,000 | | | $ | 1,859,000 | | | $ | 2,311,000 | |
| Direct patient services | | | 548,000 | | | | 304,000 | | | | 1,098,000 | | | | 546,000 | |
| Total | | $ | 1,508,000 | | | $ | 1,523,000 | | | $ | 2,957,000 | | | $ | 2,857,000 | |
| | | 2025 | | | 2024 | | | 2025 | | | 2024 | |
| Interest expense | | | | | | | | | | | | | | | | |
| Leasing | | $ | 405,000 | | | $ | 352,000 | | | $ | 803,000 | | | $ | 668,000 | |
| Direct patient services | | | 23,000 | | | | 33,000 | | | | 58,000 | | | | 66,000 | |
| Total | | $ | 428,000 | | | $ | 385,000 | | | $ | 861,000 | | | $ | 734,000 | |
| | | 2025 | | | 2024 | | | 2025 | | | 2024 | |
| Interest income | | | | | | | | | | | | | | | | |
| Leasing | | $ | 37,000 | | | $ | 77,000 | | | $ | 95,000 | | | $ | 189,000 | |
| Direct patient services | | | 11,000 | | | | - | | | | 27,000 | | | | - | |
| Total | | $ | 48,000 | | | $ | 77,000 | | | $ | 122,000 | | | $ | 189,000 | |
| | | 2025 | | | 2024 | | | 2025 | | | 2024 | |
| Income tax (benefit) expense | | | | | | | | | | | | | | | | |
| Leasing | | $ | 63,000 | | | $ | 71,000 | | | $ | (164,000 | ) | | $ | 12,000 | |
| Direct patient services | | | (84,000 | ) | | | (102,000 | ) | | | (180,000 | ) | | | (87,000 | ) |
| Total | | $ | (21,000 | ) | | $ | (31,000 | ) | | $ | (344,000 | ) | | $ | (75,000 | ) |
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| Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] |
| | | 2025 | | | 2024 | | | 2025 | | | 2024 | |
| | | | | | | | | | | | | | | | | |
| Net (loss) income attributable to American Shared Hospital Services | | | | | | | | | | | | | | | | |
| Leasing | | $ | 96,000 | | | $ | (427,000 | ) | | $ | (207,000 | ) | | $ | (258,000 | ) |
| Direct patient services | | | (376,000 | ) | | | 4,029,000 | | | | (698,000 | ) | | | 3,979,000 | |
| Total | | $ | (280,000 | ) | | $ | 3,602,000 | | | $ | (905,000 | ) | | $ | 3,721,000 | |
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| Reconciliation of Assets from Segment to Consolidated [Table Text Block] |
| | | June 30, | | | December 31, | |
| | | 2025 | | | 2024 | |
| Total assets | | | | | | | | |
| Leasing | | $ | 34,781,000 | | | $ | 35,455,000 | |
| Direct patient services | | | 28,713,000 | | | | 24,742,000 | |
| Total | | $ | 63,494,000 | | | $ | 60,197,000 | |
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