Restructuring and Separation Costs - Other Restructuring Costs (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Restructuring Reserve
Accrued, beginning of period	$ 48
Adjustments	10
Charges	8
Cash payments	(48)
Accrued, end of period	18
Separation Costs - Former Executives
Restructuring Reserve
Accrued, beginning of period	2
Adjustments	0
Charges	0
Cash payments	(2)
Accrued, end of period	0
One-Time Termination Benefits
Restructuring Reserve
Accrued, beginning of period	11
Adjustments	(1)
Charges	6
Cash payments	(15)
Accrued, end of period	1
Other Restructuring Costs
Restructuring Reserve
Accrued, beginning of period	35
Adjustments	11
Charges	2
Cash payments	(31)
Accrued, end of period	17
IT Restructuring
Restructuring Reserve
Accrued, beginning of period	0
Charges	9
Cash payments	(3)
Accrued, end of period	6
IT Restructuring \| One-Time Termination Benefits
Restructuring Reserve
Accrued, beginning of period	0
Charges	7
Cash payments	(2)
Accrued, end of period	5
IT Restructuring \| Other Restructuring Costs
Restructuring Reserve
Accrued, beginning of period	0
Charges	2
Cash payments	(1)
Accrued, end of period	$ 1

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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