Defined Benefit Plan Effect Of One Percentage Point Increase Decreased On Accumulated Postretirement Benefit Obligation.

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Defined Benefit Plan Effect Of One Percentage Point Increase Decreased On Aggregate Service And Interest Cost.

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Increase Decrease Percentage in Health assumed Health care costs.

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Pension And Other Postretirement Benefits.

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The amounts in accumulated other comprehensive income related to gains and losses that are not recognized immediately and are expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

+ References

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The amounts in accumulated other comprehensive income related to prior service cost or credit expected to be recognized as components of net periodic benefit cost over the next fiscal year that follows the most recent annual statement of financial position presented.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions.

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- Definition

The ultimate trend rate for health care costs.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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Pension and Other Postretirement Benefits (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Apr. 30, 2011	Apr. 30, 2010	Apr. 30, 2009
Pension and Other Postretirement Benefits (Textuals)
Project health care cost trend rates to decline gradually to, by 2016 and remain thereafter	5.00%
Percentage change in Health assumed Health care costs	1.00%
1% increase/decrease in assumed health care cost trend rates would have increased/decreased the accumulated postretirement benefit obligation	$ 6
1% increase/decrease in assumed health care cost trend rates would have increased/decreased the aggregate service and interest costs	1
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Reduction in benefit obligations	(24)	(23)
Expected contribution to benefit plans in 2012	40
Estimated amount of prior service cost that will be amortized from accumulated other comprehensive loss into pension expense in 2012	1
Estimated amount of net actuarial loss that will be amortized from accumulated other comprehensive loss into pension expense in 2012	19
Medical and Life Insurance Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Reduction in benefit obligations	(4)	(4)
Expected contribution to benefit plans in 2012	3
Saving Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expense For Matching Contributions	$ 9	$ 8	$ 10