|
Postretirement Benefits - Components of the Net Periodic Benefit Cost (Detail) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
|
Dec. 31, 2011
|
Dec. 31, 2010
|
Dec. 31, 2011
|
Dec. 31, 2010
|
|
|
Pension Benefits
|
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| Service Cost | $ 63 | $ 64 | $ 130 | $ 126 |
| Interest Cost | 152 | 144 | 309 | 284 |
| Expected Return on Plan Assets | (142) | (122) | (288) | (241) |
| Amortization of Deferred Amounts | 5 | 5 | 11 | 9 |
| Recognized Net Actuarial Loss | 26 | 38 | 52 | 75 |
| Gross Benefit Cost (Credit) | 104 | 129 | 214 | 253 |
| Dividends on ESOP Preferred Stock | 0 | 0 | 0 | 0 |
| Net Periodic Benefit Cost (Credit) | 104 | 129 | 214 | 253 |
|
Other Retiree Benefits
|
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| Service Cost | 35 | 35 | 71 | 70 |
| Interest Cost | 69 | 66 | 138 | 131 |
| Expected Return on Plan Assets | (108) | (107) | (216) | (215) |
| Amortization of Deferred Amounts | (5) | (5) | (10) | (10) |
| Recognized Net Actuarial Loss | 24 | 23 | 49 | 47 |
| Gross Benefit Cost (Credit) | 15 | 12 | 32 | 23 |
| Dividends on ESOP Preferred Stock | (18) | (19) | (37) | (39) |
| Net Periodic Benefit Cost (Credit) | $ (3) | $ (7) | $ (5) | $ (16) |