Basis of Presentation (Notes)	3 Months Ended
Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business Description and Basis of Presentation	1. Basis of Presentation Background - Knowles Corporation (NYSE:KN) is a leading manufacturer of specialty electronic components. The Company designs parts that perform unique and critical functions for innovative technologies. Through extreme reliability, custom engineering, and scalable manufacturing, the Company enables businesses to succeed in the most demanding applications across medtech, defense, industrial, and electrification markets. Knowles high performance capacitors, radio frequency ("RF") filters, advanced medtech microphones, and balanced armature speakers enhance the performance of customer products. The Company's focus on the customer, combined with unique technology, proprietary manufacturing techniques, and global operational expertise, enable the Company to deliver innovative solutions across multiple applications. References to "Knowles," "the Company," "we," "our," and "us" refer to Knowles Corporation and its consolidated subsidiaries. Financial Statement Presentation - The accompanying unaudited interim Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC") for quarterly reports on Form 10-Q and do not include all of the information and note disclosures required by U.S. generally accepted accounting principles (“GAAP” or “U.S. GAAP”) for complete financial statements. These unaudited interim Consolidated Financial Statements should therefore be read in conjunction with the Consolidated Financial Statements and Notes thereto for the year ended December 31, 2025 included in the Company’s Annual Report on Form 10-K. The accompanying unaudited interim Consolidated Financial Statements have been prepared in accordance with U.S. GAAP, which requires management to make estimates and assumptions that affect amounts reported in the Consolidated Financial Statements and accompanying disclosures. Although these estimates are based on management’s best knowledge of current events and actions that the Company may undertake in the future, actual results may differ from those estimates. Management uses historical experience and all available information to make these estimates. The unaudited interim Consolidated Financial Statements reflect all adjustments of a normal, recurring nature that are, in the opinion of management, necessary for a fair statement of results for these interim periods. On December 27, 2024, the Company completed the sale of the Consumer MEMS Microphones ("CMM") business to Syntiant Corp. ("Syntiant"). See Note 3. Discontinued Operations for additional information related to this transaction. The results of operations for CMM have been classified as discontinued operations for all periods presented. Transactions with Syntiant - As partial consideration for the sale of CMM on December 27, 2024, the Company received Series D-2 preferred stock of Syntiant. See Note 3. Discontinued Operations for additional information related to this transaction. The Company accounts for this investment using the cost method, measured at its historical cost, which was the fair value of the consideration received from Syntiant for the sale of CMM, plus any non-cash dividend earned. The balance of this investment was $83.4 million as of both March 31, 2026 and December 31, 2025, and is classified as “Investment in affiliate” on the Consolidated Balance Sheet. In connection with the sale of CMM, the Company provided financing of $6.4 million to Syntiant, which was utilized to fund Syntiant's requirement to have $40.0 million of cash on its balance sheet at closing. This note is junior to Syntiant's debt financing and matures on March 28, 2029 and bears interest at the prime rate until six months after the closing date of the sale, at which time the interest rate increased to 13.0%. The balance of this note was $5.9 million as of both March 31, 2026 and December 31, 2025 and is classified within "Other assets and deferred charges" on the Consolidated Balance Sheet. The Company shares in certain separation costs with Syntiant related to the sale of CMM pursuant to a credit for up to $13.5 million. Under the terms of the separation cost credit, the Company is required to reimburse Syntiant 100% for the first $7.0 million of separation costs incurred and 50% for those costs in excess of $7.0 million, up to the maximum established separation cost credit of $13.5 million. The balance of the separation credit was $4.3 million and $4.8 million at March 31, 2026 and December 31, 2025, respectively and is classified within "Other accrued expenses" on the Consolidated Balance Sheet. As the balance of the separation credit is now below the $7.0 million contractual threshold, future costs will be shared equally by the Company and Syntiant. The Company leases portions of its facilities to Syntiant, for which lease payments of $0.2 million and $1.2 million were applied to the separation credit for the three months ended March 31, 2026 and 2025, respectively. The Company also subleases portions of its manufacturing facilities to Syntiant at cost. The portion of operating lease right-of-use assets subleased by Syntiant totaled $5.2 million as of both March 31, 2026 and December 31, 2025, respectively. The Company recognized revenue totaling $2.7 million and $4.3 million during the three months ended March 31, 2026 and 2025, respectively, related to transactions with Syntiant. These revenues are reflected in the results of the MedTech & Specialty Audio segment. Receivables, net include $3.1 million and $4.2 million due from Syntiant at March 31, 2026 and December 31, 2025, respectively, related to these sales transactions and amounts related to the sale of CMM. Share Repurchase Program - On February 24, 2020, the Company announced that its Board of Directors had authorized a share repurchase program of up to $100.0 million of the Company's common stock. On April 28, 2022, the Company announced that its Board of Directors had increased the authorization by up to $150.0 million in additional aggregate value. On February 13, 2025, the Company announced another authorization increase of up to $150.0 million in additional aggregate value, for a total of $400.0 million of aggregate value. The timing and amount of any shares repurchased will be determined by the Company based on its evaluation of market conditions and other factors, and will be made in accordance with applicable securities laws in either the open market or in privately negotiated transactions. The Company is not obligated to purchase any shares under the program, and the program may be suspended or discontinued at any time. Any shares repurchased will be held as treasury stock. During the three months ended March 31, 2026 and 2025, the Company repurchased 276,309 and 300,768 shares of common stock for a total of $7.5 million and $5.0 million, respectively. At March 31, 2026, the Company had $121.5 million remaining that may yet be repurchased under the share repurchase program. Non-cash Operating Activities - Operating lease liabilities arising from obtaining right-of-use assets for the three months ended March 31, 2026 and 2025 were $1.1 million and $13.7 million, respectively. Non-cash Investing Activities - Purchases of property, plant, and equipment included in accounts payable at March 31, 2026 and 2025 were $1.9 million and $1.3 million, respectively.

Background - Knowles Corporation (NYSE:KN) is a leading manufacturer of specialty electronic components. The Company designs parts that perform unique and critical functions for innovative technologies. Through extreme reliability, custom engineering, and scalable manufacturing, the Company enables businesses to succeed in the most demanding applications across medtech, defense, industrial, and electrification markets. Knowles high performance capacitors, radio frequency ("RF") filters, advanced medtech microphones, and balanced armature speakers enhance the performance of customer products. The Company's focus on the customer, combined with unique technology, proprietary manufacturing techniques, and global operational expertise, enable the Company to deliver innovative solutions across multiple applications. References to "Knowles," "the Company," "we," "our," and "us" refer to Knowles Corporation and its consolidated subsidiaries.

Financial Statement Presentation - The accompanying unaudited interim Consolidated Financial Statements have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission ("SEC") for quarterly reports on Form 10-Q and do not include all of the information and note disclosures required by U.S. generally accepted accounting principles (“GAAP” or “U.S. GAAP”) for complete financial statements. These unaudited interim Consolidated Financial Statements should therefore be read in conjunction with the Consolidated Financial Statements and Notes thereto for the year ended December 31, 2025 included in the Company’s Annual Report on Form 10-K.

The accompanying unaudited interim Consolidated Financial Statements have been prepared in accordance with U.S. GAAP, which requires management to make estimates and assumptions that affect amounts reported in the Consolidated Financial Statements and accompanying disclosures. Although these estimates are based on management’s best knowledge of current events and actions that the Company may undertake in the future, actual results may differ from those estimates. Management uses historical experience and all available information to make these estimates. The unaudited interim Consolidated Financial Statements reflect all adjustments of a normal, recurring nature that are, in the opinion of management, necessary for a fair statement of results for these interim periods.

On December 27, 2024, the Company completed the sale of the Consumer MEMS Microphones ("CMM") business to Syntiant Corp. ("Syntiant"). See Note 3. Discontinued Operations for additional information related to this transaction. The results of operations for CMM have been classified as discontinued operations for all periods presented.

Transactions with Syntiant - As partial consideration for the sale of CMM on December 27, 2024, the Company received Series D-2 preferred stock of Syntiant. See Note 3. Discontinued Operations for additional information related to this transaction. The Company accounts for this investment using the cost method, measured at its historical cost, which was the fair value of the consideration received from Syntiant for the sale of CMM, plus any non-cash dividend earned. The balance of this investment was $83.4 million as of both March 31, 2026 and December 31, 2025, and is classified as “Investment in affiliate” on the Consolidated Balance Sheet.

In connection with the sale of CMM, the Company provided financing of $6.4 million to Syntiant, which was utilized to fund Syntiant's requirement to have $40.0 million of cash on its balance sheet at closing. This note is junior to Syntiant's debt financing and matures on March 28, 2029 and bears interest at the prime rate until six months after the closing date of the sale, at which time the interest rate increased to 13.0%. The balance of this note was $5.9 million as of both March 31, 2026 and December 31, 2025 and is classified within "Other assets and deferred charges" on the Consolidated Balance Sheet.

The Company shares in certain separation costs with Syntiant related to the sale of CMM pursuant to a credit for up to $13.5 million. Under the terms of the separation cost credit, the Company is required to reimburse Syntiant 100% for the first $7.0 million of separation costs incurred and 50% for those costs in excess of $7.0 million, up to the maximum established separation cost credit of $13.5 million. The balance of the separation credit was $4.3 million and $4.8 million at March 31, 2026 and December 31, 2025, respectively and is classified within "Other accrued expenses" on the Consolidated Balance Sheet. As the balance of the separation credit is now below the $7.0 million contractual threshold, future costs will be shared equally by the Company and Syntiant.

The Company leases portions of its facilities to Syntiant, for which lease payments of $0.2 million and $1.2 million were applied to the separation credit for the three months ended March 31, 2026 and 2025, respectively. The Company also subleases portions of its manufacturing facilities to Syntiant at cost. The portion of operating lease right-of-use assets subleased by Syntiant totaled $5.2 million as of both March 31, 2026 and December 31, 2025, respectively.

The Company recognized revenue totaling $2.7 million and $4.3 million during the three months ended March 31, 2026 and 2025, respectively, related to transactions with Syntiant. These revenues are reflected in the results of the MedTech & Specialty Audio segment. Receivables, net include $3.1 million and $4.2 million due from Syntiant at March 31, 2026 and December 31, 2025, respectively, related to these sales transactions and amounts related to the sale of CMM.

Share Repurchase Program - On February 24, 2020, the Company announced that its Board of Directors had authorized a share repurchase program of up to $100.0 million of the Company's common stock. On April 28, 2022, the Company announced that its Board of Directors had increased the authorization by up to $150.0 million in additional aggregate value. On February 13, 2025, the Company announced another authorization increase of up to $150.0 million in additional aggregate value, for a total of $400.0 million of aggregate value. The timing and amount of any shares repurchased will be determined by the Company based on its evaluation of market conditions and other factors, and will be made in accordance with applicable securities laws in either the open market or in privately negotiated transactions. The Company is not obligated to purchase any shares under the program, and the program may be suspended or discontinued at any time. Any shares repurchased will be held as treasury stock.

During the three months ended March 31, 2026 and 2025, the Company repurchased 276,309 and 300,768 shares of common stock for a total of $7.5 million and $5.0 million, respectively. At March 31, 2026, the Company had $121.5 million remaining that may yet be repurchased under the share repurchase program.

Non-cash Operating Activities - Operating lease liabilities arising from obtaining right-of-use assets for the three months ended March 31, 2026 and 2025 were $1.1 million and $13.7 million, respectively.