Stock Compensation - Performance Shares (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
Feb. 28, 2019	Mar. 30, 2019
2019 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Performance shares target grant distribution (in shares)		256,000
Grant-date fair value of shares that correspond with target grants		$ 59
2016 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance shares that may be earned upon performance	85.00%
Performance share award settlement	$ 6
Minimum [Member] \| 2019 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance shares that may be earned upon performance		0.00%
Maximum [Member] \| 2019 Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance shares that may be earned upon performance		200.00%

Performance Awards Settlement Stock Issued Value

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- Definition

Performance Share Target Grant

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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=109197908&loc=d3e5070-113901

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ 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 (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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.

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- Definition

Percentage of vesting of share-based compensation awards.

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