Commitments and Contingencies - Summary of Additional Information Related to Operating Lease Agreements (Details) $ in Millions	12 Months Ended
Mar. 31, 2020 USD ($)
Commitments And Contingencies Disclosure [Abstract]
ROU assets	$ 114
Lease liabilities	$ 120
Weighted average remaining lease term (in years)	9 years 3 months 14 days
Weighted average discount rate	3.05%
Cash paid for amounts included in the measurement of lease liabilities - operating cash flows	$ 23
ROU assets obtained in exchange for operating lease obligations	$ 17

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

+ Details

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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-Publisher FASB
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