Percentage of voting equity interests acquired at the acquisition date in 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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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 09, 2020	Dec. 31, 2019
Equity Method Investments	$ 285		$ 291
Hemlock Semiconductor LLC [Member]
Business combination ownership interest acquired		100.00%
Hemlock Semiconductor Operations LLC [Member]
Equity Method Investments		$ (250)
Business combination ownership interest acquired		80.50%
Minimum [Member]
Equity Method Investment, Ownership Percentage	20.00%
Maximum [Member]
Equity Method Investment, Ownership Percentage	50.00%