Director Deferred Stock Ownership Plan Amount to be credited to deferred stock accounts.

No definition available.

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- Definition

Share Delivery Term if Elected

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Cost Recognition Period

+ 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

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

Net number of share options (or share units) granted during the period.

+ 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=116856206&loc=d3e5070-113901

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ 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=116856206&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=116856206&loc=d3e5070-113901

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Director deferred stock ownership plan amount to be credited to deferred stock accounts (as a percent)	50.00%
Share delivery term if elected	5 years
Award vesting period	3 years
Stock options granted (shares)	0	0
Total fair value of stock options, vested	$ 3	$ 4	$ 5
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Award expiration period	10 years
Employee Stock Option \| Graded Vesting Method
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Employee Stock Option \| Ratable Vest One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award cost recognition period	12 months
Employee Stock Option \| Ratable Vest Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award cost recognition period	24 months
Employee Stock Option \| Ratable Vest Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award cost recognition period	36 months
Employee Stock Option \| Ratable Vest Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award cost recognition period	48 months