Basis of Presentation	12 Months Ended
Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	(2) Basis of Presentation The Consolidated Financial Statements include the accounts of MKS and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to current period presentation. As a result of rounding, there may be immaterial differences in amounts presented and certain calculations may not sum to the total number expressed in each category or tie to a corresponding schedule. The Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The preparation of these financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates and judgments, including those related to revenue recognition and allowance for doubtful accounts, inventory valuation, warranty costs, pension plan valuations, stock-based compensation, intangible assets, goodwill, other long-lived assets, in-process research and development (“IPR&D”) and income taxes. Management bases its estimates and judgments on historical experience and on various other factors that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. The Company has three reportable segments: the Vacuum Solutions Division (“VSD”), the Photonics Solutions Division (“PSD”) and the Materials Solutions Division (“MSD”) as described in Note 22.

Basis of Presentation

12 Months Ended

Dec. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

(2)

Basis of Presentation

The Consolidated Financial Statements include the accounts of MKS and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Certain prior period amounts have been reclassified to conform to current period presentation. As a result of rounding, there may be immaterial differences in amounts presented and certain calculations may not sum to the total number expressed in each category or tie to a corresponding schedule.

The Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The preparation of these financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, management evaluates its estimates and judgments, including those related to revenue recognition and allowance for doubtful accounts, inventory valuation, warranty costs, pension plan valuations, stock-based compensation, intangible assets, goodwill, other long-lived assets, in-process research and development (“IPR&D”) and income taxes. Management bases its estimates and judgments on historical experience and on various other factors that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

The Company has three reportable segments: the Vacuum Solutions Division (“VSD”), the Photonics Solutions Division (“PSD”) and the Materials Solutions Division (“MSD”) as described in Note 22.