Pensions and Other Postretirement Benefits
The following tables summarize the components of net periodic pension and other postretirement benefits (OPEB) (income) expense (dollars in millions): | | | | | | | | | | | | | | | | | | | | | | | | | | Three Months Ended September 30, 2015 | | Three Months Ended September 30, 2014 | | Pension Benefits | | Global OPEB Plans | | Pension Benefits | | Global OPEB Plans | | U.S. | | Non-U.S. | | | U.S. | | Non-U.S. | | Service cost | $ | 101 |
| | $ | 116 |
| | $ | 6 |
| | $ | 94 |
| | $ | 92 |
| | $ | 7 |
| Interest cost | 689 |
| | 184 |
| | 59 |
| | 765 |
| | 259 |
| | 66 |
| Expected return on plan assets | (974 | ) | | (193 | ) | | — |
| | (978 | ) | | (221 | ) | | — |
| Amortization of prior service cost (credit) | (1 | ) | | 3 |
| | (4 | ) | | (1 | ) | | 4 |
| | (4 | ) | Amortization of net actuarial (gains) losses | 2 |
| | 58 |
| | 10 |
| | (22 | ) | | 37 |
| | 2 |
| Curtailments, settlements and other | — |
| | 1 |
| | — |
| | 3 |
| | 3 |
| | — |
| Net periodic pension and OPEB (income) expense | $ | (183 | ) | | $ | 169 |
| | $ | 71 |
| | $ | (139 | ) | | $ | 174 |
| | $ | 71 |
|
| | | | | | | | | | | | | | | | | | | | | | | | | | Nine Months Ended September 30, 2015 | | Nine Months Ended September 30, 2014 | | Pension Benefits | | Global OPEB Plans | | Pension Benefits | | Global OPEB Plans | | U.S. | | Non-U.S. | | | U.S. | | Non-U.S. | | Service cost | $ | 304 |
| | $ | 311 |
| | $ | 18 |
| | $ | 285 |
| | $ | 297 |
| | $ | 18 |
| Interest cost | 2,066 |
| | 575 |
| | 178 |
| | 2,295 |
| | 784 |
| | 203 |
| Expected return on plan assets | (2,922 | ) | | (598 | ) | | — |
| | (2,935 | ) | | (662 | ) | | — |
| Amortization of prior service cost (credit) | (3 | ) | | 11 |
| | (10 | ) | | (3 | ) | | 13 |
| | (12 | ) | Amortization of net actuarial (gains) losses | 6 |
| | 175 |
| | 27 |
| | (68 | ) | | 117 |
| | 6 |
| Curtailments, settlements and other | — |
| | 108 |
| | — |
| | 1 |
| | 4 |
| | — |
| Net periodic pension and OPEB (income) expense | $ | (549 | ) | | $ | 582 |
| | $ | 213 |
| | $ | (425 | ) | | $ | 553 |
| | $ | 215 |
|
The curtailment charges recorded in the nine months ended September 30, 2015 were due primarily to the General Motors Canada Limited (GMCL) hourly pension plan that was remeasured as a result of a voluntary separation program. |