Stock-Based Compensation Introduction Narrative (Details) shares in Millions	12 Months Ended
Dec. 31, 2019 Performance_metrics shares
Shares available for future grant under the plan (in shares)	0.6
Retirement Eligibility Age	65 years
Retirement Eligibility Age with Ten Years of Service	55 years
Retirement Eligibility Years Tenure	10 years
Retirement Eligibility Service Requirement	1 year
Maximum
Shares authorized for issuance under the plan (in shares)	6.0
Restricted Stock Units
Award Vesting Period	3 years
Annual Vesting Percentage	33.33%
Performance Share Units
Award Vesting Period	3 years
Annual Vesting Percentage	33.33%
Number of performance metrics	2
The first performance metric \| Performance_metrics	1
Performance Share Units \| RTSR \| Minimum
Award Vesting Rights, Percentage	0.00%
Performance Share Units \| RTSR \| Maximum
Award Vesting Rights, Percentage	175.00%
Performance Share Units \| Cumulative Free Cash Flow \| Minimum
Award Vesting Rights, Percentage	0.00%
Performance Share Units \| Cumulative Free Cash Flow \| Maximum
Award Vesting Rights, Percentage	200.00%
Options
Award Vesting Period	4 years
Annual Vesting Percentage	25.00%
Award Expiration Period	10 years

Number of performance metrics

No definition available.

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- Definition

Age attained for which the retirement provision for equity grants provides for continued vesting of awards provided they have been employed or provided services to the Company for one year following the date of grant.

+ References

No definition available.

+ Details

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- Definition

Age attained for which the retirement provision for equity grants provides for continued vesting of awards if the employee has at least ten years of tenure with the Company and provided they have been employed or provided services to the Company for one year following the date of grant.

+ References

No definition available.

+ Details

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- Definition

Number of years of service required following the grant date or start of the performance period in order to qualify for the retirement provision for equity grants.

+ References

No definition available.

+ Details

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- Definition

Number of years of tenure with the Company required for employees aged 55 to qualify for the retirement provision for equity grants.

+ References

No definition available.

+ Details

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- Definition

Annual percentage of vesting of share-based compensation awards.

+ References

No definition available.

+ Details

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- Definition

The first performance metric

+ References

No definition available.

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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=116856206&loc=d3e5070-113901

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- Definition

Number of shares authorized for issuance 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 (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ 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
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

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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
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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