Revenue Recognition - Contract with Customer, Asset and Liability (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Customer receivables	$ 518	$ 518
Contract liabilities	282	207
Contract assets	55	64
Accounts receivable, gross	560	554
Allowance for doubtful accounts	$ 42	$ 36

Contract with Customer, Contract Liability

No definition available.

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- Definition

For unclassified balance sheet, amounts due from customers or clients for goods or services that have been delivered or sold in the normal course of business.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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- Definition

For an unclassified balance sheet, the amount due from customers or clients for goods or services that have been delivered or sold in the normal course of business, reduced to their estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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-Name Accounting Standards Codification
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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- References

No definition available.

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