Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Pension and Employee Benefit Plans, Weighted-average Asset Allocations (Details) - Pension Plans [Member] - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target allocation		100.00%
Plan assets		100.00%	100.00%
Anticipated contributions next fiscal year		$ 20
Equity Securities [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target allocation		65.00%
Plan assets		60.00%	66.00%
Debt Securities [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target allocation		21.00%
Plan assets		22.00%	19.00%
Real Estate Investments [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target allocation		13.00%
Plan assets		16.00%	12.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Target allocation		1.00%
Plan assets		2.00%	3.00%
U.S. Plans [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Expected return on plan assets		7.50%	7.50%	7.50%
U.S. Plans [Member] \| Forecast [Member]
Defined Benefit Plan, Information about Plan Assets [Abstract]
Expected return on plan assets	7.50%