| Segment Reporting [Table Text Block] |
| | | Light | | | Commercial | | | | | | | | | |
| Three Months Ended September 30, 2026 | | Vehicle | | | Vehicle | | | Corporate | | | Total | |
| External sales | | $ | 1,371 | | | $ | 667 | | | | | | | $ | 2,038 | |
| Inter-segment sales | | | 34 | | | | 21 | | | | | | | | 55 | |
| | | | 1,405 | | | | 688 | | | | | | | | 2,093 | |
| Reconciliation of sales | | | | | | | | | | | | | | | | |
| Elimination of inter-segment sales | | | | | | | | | | | | | | | (55 | ) |
| Total consolidated sales | | | | | | | | | | | | | | $ | 2,038 | |
| Less: | | | | | | | | | | | | | | | | |
| Cost of sales | | | 1,223 | | | | 583 | | | | | | | | | |
| Selling, general and administrative expenses | | | 39 | | | | 36 | | | | | | | | | |
| Other segment items (a) | | | 8 | | | | — | | | | | | | | | |
| Segment EBITDA | | $ | 151 | | | $ | 69 | | | | | | | $ | 220 | |
| | | | | | | | | | | | | | | | | |
| Purchases of property, plant and equipment | | $ | 53 | | | $ | 11 | | | $ | 6 | | | $ | 70 | |
| Segment net assets (b) - September 30, 2026 | | $ | 541 | | | $ | 500 | | | $ | (73 | ) | | $ | 968 | |
| | | Light | | | Commercial | | | | | | | | | |
| Three Months Ended September 30, 2025 | | Vehicle | | | Vehicle | | | Corporate | | | Total | |
| External sales | | $ | 1,353 | | | $ | 564 | | | | | | | $ | 1,917 | |
| Inter-segment sales | | | 33 | | | | 20 | | | | | | | | 53 | |
| | | | 1,386 | | | | 584 | | | | | | | | 1,970 | |
| Reconciliation of sales | | | | | | | | | | | | | | | | |
| Elimination of inter-segment sales | | | | | | | | | | | | | | | (53 | ) |
| Total consolidated sales | | | | | | | | | | | | | | $ | 1,917 | |
| Less: | | | | | | | | | | | | | | | | |
| Cost of sales | | | 1,214 | | | | 500 | | | | | | | | | |
| Selling, general and administrative expenses | | | 37 | | | | 32 | | | | | | | | | |
| Other segment items (a) | | | (9 | ) | | | (1 | ) | | | | | | | | |
| Segment EBITDA | | $ | 126 | | | $ | 51 | | | | | | | $ | 177 | |
| | | | | | | | | | | | | | | | | |
| Purchases of property, plant and equipment | | $ | 34 | | | $ | 13 | | | $ | 2 | | | $ | 49 | |
| Segment net assets (b) - December 31, 2025 | | $ | 465 | | | $ | 471 | | | $ | (88 | ) | | $ | 848 | |
| | | Light | | | Commercial | | | | | | | | | |
| Nine Months Ended September 30, 2026 | | Vehicle | | | Vehicle | | | Corporate | | | Total | |
| External sales | | $ | 4,019 | | | $ | 1,897 | | | | | | | $ | 5,916 | |
| Inter-segment sales | | | 86 | | | | 53 | | | | | | | | 139 | |
| | | | 4,105 | | | | 1,950 | | | | | | | | 6,055 | |
| Reconciliation of sales | | | | | | | | | | | | | | | | |
| Elimination of inter-segment sales | | | | | | | | | | | | | | | (139 | ) |
| Total consolidated sales | | | | | | | | | | | | | | $ | 5,916 | |
| Less: | | | | | | | | | | | | | | | | |
| Cost of sales | | | 3,582 | | | | 1,634 | | | | | | | | | |
| Selling, general and administrative expenses | | | 118 | | | | 110 | | | | | | | | | |
| Other segment items (a) | | | 1 | | | | (6 | ) | | | | | | | | |
| Segment EBITDA | | $ | 406 | | | $ | 200 | | | | | | | $ | 606 | |
| | | | | | | | | | | | | | | | | |
| Purchases of property, plant and equipment | | $ | 142 | | | $ | 119 | | | $ | 13 | | | $ | 274 | |
| | | Light | | | Commercial | | | | | | | | | |
| Nine Months Ended September 30, 2025 | | Vehicle | | | Vehicle | | | Corporate | | | Total | |
| External sales | | $ | 3,901 | | | $ | 1,732 | | | | | | | $ | 5,633 | |
| Inter-segment sales | | | 104 | | | | 62 | | | | | | | | 166 | |
| | | | 4,005 | | | | 1,794 | | | | | | | | 5,799 | |
| Reconciliation of sales | | | | | | | | | | | | | | | | |
| Elimination of inter-segment sales | | | | | | | | | | | | | | | (166 | ) |
| Total consolidated sales | | | | | | | | | | | | | | $ | 5,633 | |
| Less: | | | | | | | | | | | | | | | | |
| Cost of sales | | | 3,570 | | | | 1,552 | | | | | | | | | |
| Selling, general and administrative expenses | | | 122 | | | | 101 | | | | | | | | | |
| Other segment items (a) | | | (7 | ) | | | (2 | ) | | | | | | | | |
| Segment EBITDA | | $ | 306 | | | $ | 139 | | | | | | | $ | 445 | |
| | | | | | | | | | | | | | | | | |
| Purchases of property, plant and equipment | | $ | 113 | | | $ | 29 | | | $ | 11 | | | $ | 153 | |
|
| Segment Reporting, Reconciliation of Profit (Loss) by Segment to Consolidated [Table Text Block] |
| | | Three Months Ended | | | Nine Months Ended | |
| | | September 30, | | | September 30, | |
| | | 2026 | | | 2025 | | | 2026 | | | 2025 | |
| Segment EBITDA | | $ | 220 | | | $ | 177 | | | $ | 606 | | | $ | 445 | |
| Corporate expense and other items, net | | | (2 | ) | | | (15 | ) | | | (10 | ) | | | (43 | ) |
| Depreciation | | | (84 | ) | | | (86 | ) | | | (250 | ) | | | (257 | ) |
| Amortization | | | (2 | ) | | | (3 | ) | | | (7 | ) | | | (9 | ) |
| Non-service cost components of pension and OPEB costs | | | | | | | (3 | ) | | | (4 | ) | | | (7 | ) |
| Restructuring charges, net | | | (5 | ) | | | (4 | ) | | | (20 | ) | | | (17 | ) |
| Stock compensation expense | | | (9 | ) | | | (8 | ) | | | (28 | ) | | | (31 | ) |
| Strategic transaction expenses | | | (20 | ) | | | (6 | ) | | | (40 | ) | | | (12 | ) |
| Loss on sale of property, plant and equipment | | | | | | | (1 | ) | | | | | | | | |
| Supplier capacity charge adjustment | | | | | | | 2 | | | | | | | | 21 | |
| Amounts attributable to previously closed/divested operations | | | | | | | | | | | (1 | ) | | | | |
| Distressed supplier costs | | | | | | | | | | | (2 | ) | | | | |
| Loss on divestiture of ownership interests | | | | | | | | | | | (8 | ) | | | (7 | ) |
| Electric vehicle program termination charges | | | (1 | ) | | | | | | | (65 | ) | | | | |
| Foreign exchange gain (loss) on unhedged intercompany loans | | | (4 | ) | | | | | | | 19 | | | | | |
| Other items | | | (1 | ) | | | | | | | (3 | ) | | | (6 | ) |
| Earnings from continuing operations before interest and income taxes | | | 92 | | | | 53 | | | | 187 | | | | 77 | |
| Loss on extinguishment of debt | | | (24 | ) | | | | | | | (31 | ) | | | | |
| Interest income | | | 4 | | | | 3 | | | | 14 | | | | 8 | |
| Interest expense | | | 20 | | | | 47 | | | | 63 | | | | 130 | |
| Earnings (loss) from continuing operations before income taxes | | $ | 52 | | | $ | 9 | | | $ | 107 | | | $ | (45 | ) |
|
| Segment Reporting, Reconciliation of Asset by Segment to Consolidated [Table Text Block] |
| | | September 30, | | | | December 31, | |
| | | 2026 | | | 2025 | |
| Segment net assets | | $ | 968 | | | $ | 848 | |
| Accounts payable | | | 1,317 | | | | 1,154 | |
| Cash and cash equivalents | | | 321 | | | | 469 | |
| Accounts receivable - Other | | | 314 | | | | 254 | |
| Other current assets | | | 228 | | | | 114 | |
| Current assets of disposal group held for sale | | | 37 | | | | 1,029 | |
| Intangibles | | | 56 | | | | 71 | |
| Deferred tax assets | | | 500 | | | | 534 | |
| Other noncurrent assets | | | 133 | | | | 102 | |
| Investment in affiliates | | | 114 | | | | 102 | |
| Operating lease assets | | | 166 | | | | 305 | |
| Property, plant and equipment, net | | | 1,916 | | | | 1,872 | |
| Noncurrent assets of disposal group held for sale | | | 8 | | | | 954 | |
| Total assets | | $ | 6,078 | | | $ | 7,808 | |
|