Share-based Compensation [Line Items]

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Long-term Incentive Compensation (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Stock Based Compensation 2013 Plan
Long-term Incentive Compensation [Line Items]
Service period				3 years
Stock options
Long-term Incentive Compensation [Line Items]
Vesting period				3 years
Expiration period				7 years
Restricted stock
Long-term Incentive Compensation [Line Items]
Vesting period				4 years
Performance units
Long-term Incentive Compensation [Line Items]
Vesting period				3 years	3 years	3 years
Weighted average period over which unrecognized cost is recognized, years				2 years 2 months 12 days
Liability classified awards, unrecognized compensation costs				$ 14
Restricted stock units
Long-term Incentive Compensation [Line Items]
Vesting period	4 years	4 years	4 years
Weighted average period over which unrecognized cost is recognized, years				2 years 6 months
Liability classified awards, unrecognized compensation costs				$ 21
Performance cash awards
Long-term Incentive Compensation [Line Items]
Vesting period				4 years
Weighted average period over which unrecognized cost is recognized, years				3 years 4 months 24 days
Liability classified awards, unrecognized compensation costs				$ 16
Share-based payment arrangement
Long-term Incentive Compensation [Line Items]
Equity-classified awards, unrecognized compensation cost				$ 2
Weighted average period over which unrecognized cost is recognized, years				6 months