Revenue Recognition - Cumulative Effect - Consolidated Statement of Cash Flows (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in assets and liabilities, net of acquisitions:
Receivables, net of allowance	$ (58)	$ (12)	$ 18
Inventories	(34)	(21)	6
Current liabilities, exclusive of debt	(22)	$ (25)	$ 23
Balances Without Adoption of Topic 606
Changes in assets and liabilities, net of acquisitions:
Receivables, net of allowance	(51)
Inventories	(79)
Current liabilities, exclusive of debt	16
ASU 2014-09 \| Adjustments
Changes in assets and liabilities, net of acquisitions:
Receivables, net of allowance	(7)
Inventories	45
Current liabilities, exclusive of debt	$ (38)

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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The increase (decrease) during the reporting period in the aggregate amount of liabilities that result from activities that generate operating income.

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- Definition

The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities.

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