Contingent Liabilities (Narrative) (Details) $ in Millions	3 Months Ended
Jun. 30, 2021 USD ($)
Loss Contingencies [Line Items]
Estimated Litigation Liability	$ 15
Proceeds from Legal Settlements	8
Pending Litigation \| Minimum
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	0
Pending Litigation \| Maximum
Loss Contingencies [Line Items]
Loss contingency, estimate of possible loss	$ 48

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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-Name Accounting Standards Codification
-Topic 450
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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.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

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-SubTopic 20
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
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