The components of net periodic benefit cost for defined benefit plans are as follows: | | | | | | | | | | | | | | | | | | Pension Benefits | | Other Retiree Benefits | | Three Months Ended December 31 | | Three Months Ended December 31 | Amounts in millions | 2011 | | 2010 | | 2011 | | 2010 | Service cost | $ | 63 |
| | $ | 64 |
| | $ | 35 |
| | $ | 35 |
| Interest cost | 152 |
| | 144 |
| | 69 |
| | 66 |
| Expected return on plan assets | (142 | ) | | (122 | ) | | (108 | ) | | (107 | ) | Amortization of deferred amounts | 5 |
| | 5 |
| | (5 | ) | | (5 | ) | Recognized net actuarial loss | 26 |
| | 38 |
| | 24 |
| | 23 |
| Gross benefit cost (credit) | 104 |
| | 129 |
| | 15 |
| | 12 |
| Dividends on ESOP preferred stock | — |
| | — |
| | (18 | ) | | (19 | ) | Net periodic benefit cost (credit) | $ | 104 |
| | $ | 129 |
| | $ | (3 | ) | | $ | (7 | ) |
| | | | | | | | | | | | | | | | | | Pension Benefits | | Other Retiree Benefits | | Six Months Ended December 31 | | Six Months Ended December 31 | Amounts in millions | 2011 | | 2010 | | 2011 | | 2010 | Service cost | $ | 130 |
| | $ | 126 |
| | $ | 71 |
| | $ | 70 |
| Interest cost | 309 |
| | 284 |
| | 138 |
| | 131 |
| Expected return on plan assets | (288 | ) | | (241 | ) | | (216 | ) | | (215 | ) | Amortization of deferred amounts | 11 |
| | 9 |
| | (10 | ) | | (10 | ) | Recognized net actuarial loss | 52 |
| | 75 |
| | 49 |
| | 47 |
| Gross benefit cost (credit) | 214 |
| | 253 |
| | 32 |
| | 23 |
| Dividends on ESOP preferred stock | — |
| | — |
| | (37 | ) | | (39 | ) | Net periodic benefit cost (credit) | $ | 214 |
| | $ | 253 |
| | $ | (5 | ) | | $ | (16 | ) |
|