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- Definition

Business Combination, Step Acquisition, Income Tax Expense (Benefit)

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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.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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ACQUISITIONS (Ownership Restructure of Dow Corning) (Details) - USD ($) $ in Millions			3 Months Ended		12 Months Ended
	Jun. 01, 2016	May 31, 2016	Aug. 31, 2016	Jun. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Equity method investments					$ 3,320	$ 3,107	$ 2,974
Remeasurement gain (loss)							1,389
Amortization of Merger-related inventory step-up					2	120	0
Goodwill					9,846	9,833	7,541
Dow Silicones Corporation
Business Acquisition [Line Items]
Percentage of voting interests acquired	50.00%
Payments to acquire Businesses	$ 4,800
Recognized tax benefit				$ 93
Amortization of Merger-related inventory step-up							213
Goodwill	2,251
Dow Silicones Corporation
Business Acquisition [Line Items]
Equity method investments	$ 1,968
Ownership percentage		50.00%
Dow Silicones Corporation
Business Acquisition [Line Items]
Proceeds from issuance of debt		$ 4,500
Dow Silicones Corporation \| Corning Incorporated \| SplitCo
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent	100.00%
Performance Materials & Coatings [Member]
Business Acquisition [Line Items]
Equity method investments					99	103	280
Remeasurement gain (loss)							1,389
Goodwill					3,650	$ 3,689	$ 4,938
Performance Materials & Coatings [Member] \| Dow Silicones Corporation
Business Acquisition [Line Items]
Remeasurement gain (loss)				$ 1,617	$ (20)
Amortization of Merger-related inventory step-up			$ 213