Number of Major Product Categories

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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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- Definition

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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No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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No definition available.

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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- Definition

Number of shares that have been repurchased and retired during the period.

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Business And Summary Of Significant Accounting Policies (Narrative) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 31, 2021	Apr. 26, 2018
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Stock Repurchased and Retired During Period, Shares	6,662,421	4,658,544	3,328,574
Sale of Stock (in dollars per share)					$ 15.00
Shares, Issued					38,097,525
Number of Major Product Categories	2
GrafTech International Ltd \| Brookfield \| GrafTech International Ltd
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Equity Method Investment, Ownership Percentage	24.90%	24.30%		24.00%