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The increase (decrease) during the reporting period in the aggregate amount of obligations to be paid to the following types of related parties: a parent company and its subsidiaries; subsidiaries of a common parent; an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management; an entity and its principal owners, management, or member of their immediate families; affiliates; or other parties with the ability to exert significant influence.

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Contingencies - Narratives (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
Contingencies - Narratives (Details) $ in Thousands	Jun. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) shares	May 31, 2021	Dec. 31, 2020 USD ($)
Loss Contingencies [Line Items]
Related Party Tax Agreement Percent Of Savings			85.00%
Due to Related Parties			$ 19,300		$ 40,900
Related party payable - tax receivable agreement			3,828		21,752
Related party payable - tax receivable agreement long-term			15,455		$ 19,098
Increase (Decrease) in Due to Related Parties			$ 200
Change in Control, Ownership Percentage Disposal, Threshold			100.00%
Plan
Loss Contingencies [Line Items]
Equity Method Investment, Ownership Percentage	30.00%	30.00%	30.00%
GrafTech International Ltd [Member] \| Brookfield [Member]
Loss Contingencies [Line Items]
Equity Method Investment, Ownership Percentage			24.30%	24.00%	55.30%
LTIP
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		$ 73,400
Loss Contingency Accrual, Payments			$ 71,400
LTIP \| Cost of sales
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		30,700
LTIP \| Selling, General and Administrative Expenses
Loss Contingencies [Line Items]
Loss Contingency, Loss in Period		$ 42,700
Fixed Price LTAs
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	$ 61,000
London Interbank Offered Rate (LIBOR) [Member]
Loss Contingencies [Line Items]
Due to Related Party, Basis Spread on Variable Rate			0.0100
Profit Units \| LTIP
Loss Contingencies [Line Items]
Number of Shares Authorized (in shares) \| shares			30,000
Award vesting period			5 years