Shareholders' Equity, Earnings Per Share And Stock-Based Compensation [Line Items]

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- Definition

Stock Repurchase Program, Total Number of Shares Repurchased To Date

+ References

No definition available.

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- Definition

Stock Repurchase Program, Total Shares Repurchased To Date, Amount

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ 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=109197908&loc=d3e5070-113901

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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 number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ 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

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ 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)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Earnings (Loss) Per Share, Stock-Based Compensation and Share Repurchase Plan (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018	Dec. 31, 2015	Dec. 31, 2014
Shareholders' Equity, Earnings Per Share And Stock-Based Compensation [Line Items]
Number outstanding (in shares)	1,810,561	1,443,897
Number of shares authorized to be repurchased (in shares)				10,000,000
Total number of shares repurchased to date (in shares)	0		2,000,000.0
Total shares repurchased to date, amount			$ 100
Restricted Stock Units (RSUs) [Member]
Shareholders' Equity, Earnings Per Share And Stock-Based Compensation [Line Items]
Compensation cost not yet recognized	$ 14
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Shareholders' Equity, Earnings Per Share And Stock-Based Compensation [Line Items]
Award vesting period	1 year
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Shareholders' Equity, Earnings Per Share And Stock-Based Compensation [Line Items]
Award vesting period	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Terms of Award	three years