Note 3 - HSG Transactions and Acquisitions - Net Gain on Previously Owned Equity (Details) - HSG [Member] $ in Millions	Sep. 09, 2020 USD ($)
Fair value of previously held equity investment	$ 250
Equity investment liability balance as of acquisition date	(248)
Corning's gain on previously held equity investment	$ 498

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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