The maximum amount of compensation that a plan participant is allowed to defer of their eligible compensation.

No definition available.

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- Definition

Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets, Measurement Period

+ References

No definition available.

+ Details

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- Definition

The number of shares of common stock included in the defined contribution plans at the fiscal year-end.

+ References

No definition available.

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- Definition

Defined Contribution Plan, Employers Matching Contribution, Vesting Period

+ References

No definition available.

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- Definition

Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement.

+ References

No definition available.

+ Details

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- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

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- Definition

Amount, after tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669686-108580

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- Definition

Amount of cost of providing special or contractual termination benefits payable from defined benefit plan.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (s)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Details

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Pension and Other Benefit Plans - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019	Oct. 26, 2018
Defined Benefit Plan Disclosure [Line Items]
Measurement period used to calculate long-term rate of return on assets	30 years
Prior service cost				$ 28
Vesting period	1 year
Defined contribution plan contribution	$ 221	$ 192	$ 219
Shares of company common stock held in defined contribution plan assets (in shares)	3,046,140
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Contractual termination benefits	$ 13	10	3
Estimated future amortization of prior service credit	$ 9
Non-employee directors
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation plan, maximum deferral percentage	100.00%
Deferred compensation plan, liability	$ 42	48
Deferred compensation plan, expense	$ 8	$ 0	$ 2