Acquisition of Business (Fair Values of Assets and Liabilities Assumed) (Details) $ in Thousands	Jan. 16, 2024 USD ($)
Business Combination [Line Items]
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent	$ 16,000
Business Combination, Acquired Receivable, Purchased without Credit Deterioration, Fair Value	6,000
Business Combination, Recognized Asset Acquired, Inventory, Current	25,000
Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current	3,000
Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment	111,000
neu:BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsIncludingGoodwill	650,000
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent	5,000
Business Combination, Recognized Liability Assumed, Accounts Payable, Current	(3,000)
Business Combination, Recognized Liability Assumed, Other Liability, Current	(5,000)
Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent	(111,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Including Goodwill	$ 697,000

Amount of intangible assets and goodwill, recognized at the acquisition date.

No definition available.

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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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- Definition

Fair value of receivable purchased without credit deterioration, acquired in business combination. Excludes purchased financial asset with credit deterioration.

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Amount of cash and cash equivalent acquired in business combination and recognized at acquisition date.

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Amount of prepaid expense and asset classified as other, acquired in business combination and recognized at acquisition date, classified as current.

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Amount of accounts payable assumed in business combination and recognized at acquisition date, classified as current.

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Amount of liability assumed in business combination and recognized at acquisition date, classified as other and current.

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Amount of inventory acquired in business combination and recognized at acquisition date, classified as current.

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Amount of liability assumed in business combination and recognized at acquisition date, classified as other and noncurrent.

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Amount of property, plant, and equipment acquired in business combination and recognized at acquisition date.

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Amount of asset acquired in excess of (less than) liability assumed plus goodwill in business combination and recognized at acquisition date.

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