Knowles (KN) 10-K 9 Feb 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2021	Feb. 07, 2022	Jun. 30, 2021
Cover [Abstract]
Title of 12(b) Security	Common stock, $0.01 par value per share
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	90-1002689
Entity Address, Address Line One	1151 Maplewood Drive,
Document Annual Report	true
Entity Address, City or Town	Itasca
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60143
Trading Symbol	KN
Security Exchange Name	NYSE
Document Transition Report	false
City Area Code	630
Document Period End Date	Dec. 31, 2021
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Current Fiscal Year End Date	--12-31
Local Phone Number	250-5100
Entity File Number	001-36102
Entity Registrant Name	Knowles Corporation
Entity Central Index Key	0001587523
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Public Float			$ 1,791,000,000
Entity Common Stock, Shares Outstanding		91,813,002
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Document Type	10-K
Amendment Flag	false

Auditor (Details)

Auditor (Details)	12 Months Ended
	Dec. 31, 2021
Auditor [Line Items]
Auditor Name	PricewaterhouseCoopers LLP
Auditor Location	Chicago, Illinois
Auditor Firm ID	238

CONSOLIDATED STATEMENTS OF EARN

CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Revenues		$ 868.1	$ 764.3	$ 854.8
Cost of goods sold		508.6	490.8	525.1
Restructuring charges - cost of goods sold		0	2.3	1.7
Gross Profit, Total		359.5	271.2	328
Research and development expenses		92.8	92.9	96.8
Selling and administrative expenses		146.4	131.5	145.7
Total impairment charges		4	7.6	0
Restructuring charges		0.5	10	4.3
Operating expenses		243.7	242	246.8
Operating earnings		115.8	29.2	81.2
Interest expense, net		14.2	16.4	14.5
Other (income) expense, net		(3)	1.5	0.4
(Benefit from) provision for income taxes		(45.6)	8.4	16.6
Earnings from continuing operations		150.2	2.9	49.7
Earnings (loss) from discontinued operations, net		0.2	3.7	(0.6)
Net earnings		$ 150.4	$ 6.6	$ 49.1
Earnings per share:
Income (Loss) from Continuing Operations, Per Basic Share		$ 1.63	$ 0.03	$ 0.55
Income (Loss) from Continuing Operations, Per Diluted Share		1.59	0.03	0.53
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share		0	0.04	0
Earnings Per Share, Basic		1.63	0.07	0.54
Earnings Per Share, Diluted		$ 1.59	$ 0.07	$ 0.53
Weighted-average common shares outstanding:
Basic (in shares)	[1]	92,300,000	91,700,000	91,200,000
Diluted (in shares)	[1]	94,700,000	92,900,000	93,400,000
(Loss) earnings before income taxes	[2]	$ 104.6	$ 11.3	$ 66.3
[1]	Years Ended December 31, 2021 2020 2019 Revenues $ 868.1 $ 764.3 $ 854.8 Cost of goods sold 508.6 490.8 525.1 Restructuring charges - cost of goods sold — 2.3 1.7 Gross profit 359.5 271.2 328.0 Research and development expenses 92.8 92.9 96.8 Selling and administrative expenses 146.4 131.5 145.7 Impairment charges 4.0 7.6 — Restructuring charges 0.5 10.0 4.3 Operating expenses 243.7 242.0 246.8 Operating earnings 115.8 29.2 81.2 Interest expense, net 14.2 16.4 14.5 Other (income) expense, net (3.0) 1.5 0.4 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations 150.2 2.9 49.7 Earnings (loss) from discontinued operations, net 0.2 3.7 (0.6) Net earnings $ 150.4 $ 6.6 $ 49.1 Earnings per share from continuing operations: Basic $ 1.63 $ 0.03 $ 0.55 Diluted $ 1.59 $ 0.03 $ 0.53 Earnings (loss) per share from discontinued operations: Basic $ — $ 0.04 $ (0.01) Diluted $ — $ 0.04 $ — Net earnings per share: Basic $ 1.63 $ 0.07 $ 0.54 Diluted $ 1.59 $ 0.07 $ 0.53 Weighted-average common shares outstanding: Basic 92.3 91.7 91.2 Diluted 94.7 92.9 93.4
[2]	Years Ended December 31, (in millions) 2021 2020 2019 Revenues: Audio $ 667.0 $ 591.2 $ 682.8 Precision Devices 201.1 173.1 172.0 Total revenues $ 868.1 $ 764.3 $ 854.8 Earnings from continuing operations before interest and income taxes: Audio $ 137.0 $ 44.9 $ 107.3 Precision Devices 43.7 31.7 30.4 Total segments 180.7 76.6 137.7 Corporate expense / other 61.9 48.9 56.9 Interest expense, net 14.2 16.4 14.5 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Depreciation and amortization: Audio $ 46.2 $ 47.0 $ 41.3 Precision Devices 13.3 10.5 9.9 Corporate 3.0 3.1 3.2 Total $ 62.5 $ 60.6 $ 54.4 Capital expenditures: Audio $ 40.8 $ 21.9 $ 24.0 Precision Devices 5.6 9.6 16.5 Corporate 2.2 0.4 0.7 Total $ 48.6 $ 31.9 $ 41.2 Research and development: Audio $ 81.8 $ 84.6 $ 90.8 Precision Devices 10.5 6.7 5.8 Corporate 0.5 1.6 0.2 Total $ 92.8 $ 92.9 $ 96.8

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net earnings	$ 150.4	$ 6.6	$ 49.1
Other comprehensive earnings (loss), net of tax
Foreign currency translation	(3.6)	13.8	1.3
Employee benefit plans:
Actuarial gains (losses) and prior service costs arising during period	4.3	(4)	(3.7)
Amortization or settlement of actuarial losses and prior service costs	0.7	0.6	0.5
Net change in employee benefit plans	5	(3.4)	(3.2)
Changes in fair value of cash flow hedges:
Unrealized net gains (losses) arising during period	0.3	2	0.2
Net (gains) losses reclassified into earnings	(1.6)	(0.9)	0.7
Total cash flow hedges	(1.3)	1.1	0.9
Other comprehensive earnings (loss), net of tax	0.1	11.5	(1)
Comprehensive earnings	$ 150.5	$ 18.1	$ 48.1

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 68.9	$ 147.8
Accounts Receivable, after Allowance for Credit Loss, Current	146.6	131.4
Inventories, net	153.1	130.1
Prepaid and other current assets	11.7	10.3
Total current assets	380.3	419.6
Property, plant, and equipment, net	200.8	191.5
Goodwill	941.3	910
Intangible assets, net	97.3	78.7
Operating Lease, Right-of-Use Asset	17.4	23.3
Other assets and deferred charges	94.5	31.8
Total assets	1,731.6	1,654.9
Long-term Debt, Current Maturities	0	165.1
Current liabilities:
Accounts payable	90.9	70.3
Accrued compensation and employee benefits	42.8	30.4
Operating Lease, Liability, Current	11.4	10.2
Other accrued expenses	19.4	18.6
Federal and other taxes on income	1.7	2.7
Total current liabilities	166.2	297.3
Long-term debt	70	0
Deferred Income Tax Liabilities, Net	0.6	2
Operating Lease, Liability, Noncurrent	14.7	18.7
Long-term operating lease liabilities	20.6	32.8
Disposal Group, Including Discontinued Operation, Liabilities	0	0.6
Commitments and contingencies (Note 15)
Stockholders' equity:
Preferred Stock, Value, Issued	0	0
Common Stock, Value, Issued	1	0.9
Additional paid-in capital	1,639.4	1,587.8
Accumulated deficit	(18.1)	(168.5)
Accumulated other comprehensive loss	(100.4)	(100.5)
Total stockholders' equity	1,459.5	1,303.5
Total equity	1,459.5	1,303.5
Total liabilities and stockholders' equity	$ 1,731.6	$ 1,654.9
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	95,112,778	92,689,912
Common Stock, Shares, Outstanding	91,894,980	91,611,549
Treasury Stock, Shares	3,217,798	1,078,363
Document Period End Date	Dec. 31, 2021
Treasury Stock, Value	$ (62.4)	$ (16.2)

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Allowance for doubtful accounts receivable	$ 0.2	$ 1.6	$ 0.8
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	95,112,778	92,689,912
Common Stock, Shares, Outstanding	91,894,980	91,611,549
Treasury Stock, Shares	3,217,798	1,078,363

CONSOLIDATED STATEMENT OF STOCK

CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY - USD ($) $ in Millions	Total	Amount	Treasury Stock [Member]	Treasury Stock [Member]Convertible Notes Due Twenty Twenty One [Member]Convertible Debt	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Convertible Notes Due Twenty Twenty One [Member]Convertible Debt
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares issued (in shares)		90,212,779
Treasury Stock, Shares			0
Balance at Dec. 31, 2018	$ 1,211.6	$ 0.9	$ 0		$ (111)	$ (224.2)	$ 1,545.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	49.1					49.1
Other Comprehensive Income (Loss), Net of Tax	(1)				(1)
Exercise of convertible note hedges	25.2						25.2
Stock Issued During Period, Shares, New Issues		623,951
Restricted and performance stock unit settlement, net of tax	(6.4)						(6.4)
Exercise of stock options	10						10
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings		865,015
Balance at Dec. 31, 2019	1,288.5	$ 0.9	$ 0		(112)	(175.1)	1,574.7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock, shares issued (in shares)		91,701,745
Treasury Stock, Shares			0
Net earnings	6.6					6.6
Other Comprehensive Income (Loss), Net of Tax	11.5				11.5
Stock Repurchased During Period, Value			$ 16.2
Stock Repurchased During Period, Shares			(1,078,363)
Exercise of convertible note hedges	17.3						17.3
Stock Issued During Period, Shares, New Issues		141,336
Restricted and performance stock unit settlement, net of tax	(6.1)						(6.1)
Exercise of stock options	1.9						1.9
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings		846,831
Balance at Dec. 31, 2020	1,303.5	$ 0.9	$ (16.2)		(100.5)	(168.5)	1,587.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retained Earnings (Accumulated Deficit)	$ (168.5)
Common stock, shares issued (in shares)	92,689,912	92,689,912
Treasury Stock, Shares	1,078,363		(1,078,363)
Net earnings	$ 150.4
Other Comprehensive Income (Loss), Net of Tax	0.1				0.1
Stock Repurchased During Period, Value			$ 44.5
Stock Repurchased During Period, Shares			(2,139,413)
Exercise of convertible note hedges	32.1						32.1
Stock Issued During Period, Shares, New Issues		1,540,314
Restricted and performance stock unit settlement, net of tax	(7.7)						(7.7)
Exercise of stock options	25.6	$ 0.1					25.5
Stock Issued During Period, Value, Conversion of Convertible Securities	0		$ 5.9
Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature							(5.9)
Stock Issued During Period, Shares, Conversion of Convertible Securities			363,579
Shares received from convertible note hedges				(363,601)
Exercise of convertible note hedges	0			$ (7.6)				$ 7.6
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings		882,552
Balance at Dec. 31, 2021	1,459.5	$ 1	$ (62.4)		$ (100.4)	$ (18.1)	$ 1,639.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Retained Earnings (Accumulated Deficit)	$ (18.1)
Common stock, shares issued (in shares)	95,112,778	95,112,778
Treasury Stock, Shares	3,217,798		(3,217,798)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Activities
Net earnings	$ 150,400,000	$ 6,600,000	$ 49,100,000
Adjustments to reconcile net earnings to cash from operating activities:
Depreciation and amortization	62,500,000	60,600,000	54,400,000
Stock-based compensation	32,100,000	17,300,000	25,200,000
Non-cash interest expense and amortization of debt issuance costs	8,000,000	8,900,000	8,100,000
Total impairment charges	4,000,000	7,600,000	0
Impaired Assets to be Disposed of by Method Other than Sale, Amount of Impairment Loss	0	1,700,000	0
Gain (Loss) on Disposition of Property Plant Equipment	0	300,000	200,000
Deferred income taxes	(61,200,000)	(2,600,000)	(700,000)
Other, net	0	5,000,000	1,300,000
Changes in assets and liabilities (excluding effects of foreign exchange):
Receivables, net	(12,300,000)	29,000,000	(17,800,000)
Inventories, net	(20,700,000)	16,700,000	(300,000)
Prepaid and other current assets	(2,900,000)	(100,000)	2,700,000
Accounts payable	17,200,000	(17,500,000)	12,100,000
Accrued compensation and employee benefits	11,900,000	(2,100,000)	(8,100,000)
Other accrued expenses	1,800,000	2,600,000	(600,000)
Accrued taxes	(1,100,000)	(5,800,000)	2,700,000
Other non-current assets and non-current liabilities	(7,600,000)	(100,000)	(4,400,000)
Net cash provided by operating activities	182,100,000	128,100,000	123,900,000
Investing Activities
Payments for (Proceeds from) Investments	(3,500,000)	(3,500,000)	0
Proceeds from the sale of property, plant, and equipment	600,000	300,000	0
Proceeds from Sale of Short-term Investments	400,000	0	0
Additions to property, plant, and equipment	(48,600,000)	(31,900,000)	(41,200,000)
Acquisitions of business (net of cash acquired)	(78,500,000)	0	(69,300,000)
Net cash used in investing activities	(129,600,000)	(35,100,000)	(110,500,000)
Financing Activities
Payments under revolving credit facility	0	(100,000,000)	(19,000,000)
Borrowings under revolving credit facility	70,000,000	100,000,000	10,000,000
Payments for Repurchase of Common Stock	(44,500,000)	(16,200,000)	0
Payments of debt issuance costs	0	(1,400,000)	0
Payment for Contingent Consideration Liability, Financing Activities	0	0	(1,200,000)
Payments of finance lease obligations	(2,300,000)	(2,000,000)	(1,700,000)
Tax on restricted and performance stock unit vesting	(7,700,000)	(6,100,000)	(6,400,000)
Proceeds from exercise of stock-based awards	25,600,000	1,800,000	9,800,000
Net cash used in financing activities	(131,400,000)	(23,900,000)	(8,500,000)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	0	300,000	0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect, Total	(78,900,000)	69,400,000	4,900,000
Cash and Cash Equivalents, at Carrying Value, Including Discontinued Operations	68,900,000	147,800,000	78,400,000
Supplemental information - cash paid during the year for:
Income taxes	16,100,000	16,800,000	12,100,000
Interest	7,400,000	8,100,000	7,500,000
Convertible Notes Due Twenty Twenty One [Member] | Convertible Debt
Financing Activities
Proceeds from issuance of warrants	39,100,000
Purchase of convertible note hedges	(44,500,000)
Supplemental information - cash paid during the year for:
Debt instrument, face amount	172,500,000	0	0
Debt instrument, face amount	$ 172,500,000	$ 0	$ 0

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies Background - Knowles Corporation (NYSE:KN) is a market leader and global provider of advanced micro-acoustic microphones and balanced armature speakers, audio solutions, and high performance capacitors and radio frequency ("RF") products, serving the consumer electronics, medtech, defense, electric vehicle, industrial, and communications markets. The Company uses its leading position in SiSonic TM micro-electro-mechanical systems ("MEMS") microphones and strong capabilities in audio processing technologies to optimize audio systems and improve the user experience across consumer applications. Knowles is also a leader in hearing health acoustics, high performance capacitors, and RF solutions for a diverse set of markets. The Company's focus on the customer, combined with its 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. On May 3, 2021, the Company acquired all of the outstanding shares of common stock of Integrated Microwave Corporation ("IMC"), a manufacturer of RF filters. See Note 3. Acquisitions for additional information related to the transaction. On February 24, 2020, the Company announced that its Board of Directors had authorized a share repurchase program of up to $100 million of the Company's common stock. 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. The actual timing, number, and share price of shares repurchased will depend on a number of factors, including the market price of the Company’s common stock, general market and economic conditions, and applicable legal requirements. Any shares repurchased will be held as treasury stock. During the years ended December 31, 2021 and 2020, the Company repurchased 2,139,413 shares and 1,078,363 shares of common stock, respectively, for a total of $44.5 million and $16.2 million, respectively. On December 20, 2019, the Company acquired substantially all of the assets of the MEMS Microphone Application-specific integrated circuit Design Business (“ASIC Design Business”). See Note 3. Acquisitions for additional information related to the transaction. On January 3, 2019, the Company acquired substantially all of the assets of DITF Interconnect Technology, Inc. ("DITF"), a thin film components manufacturer. See Note 3. Acquisitions for additional information related to the transaction. Financial Statement Presentation - The Consolidated Financial Statements included in this Annual Report on Form 10-K are presented in conformity with U.S. generally accepted accounting principles ("U.S. GAAP"). Use of Estimates - The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying financial statements and disclosures. These estimates may be adjusted due to changes in future economic, industry, or customer financial conditions, as well as changes in technology or demand. Estimates are used in accounting for, among other items, inventory reserves, restructuring reserves, warranty reserves, pension and post-retirement plans, stock-based compensation, useful lives for depreciation and amortization of long-lived assets, future cash flows associated with impairment testing for goodwill, indefinite-lived intangible assets and other long-lived assets, deferred tax assets, uncertain income tax positions, changes in tax laws, and contingencies. Management uses historical experience and all available information to make these estimates, including considerations for the impact of the COVID-19 pandemic on the macroeconomic environment. The situation related to the COVID-19 pandemic continues to be complex and dynamic. The Company cannot reasonably estimate the duration of the COVID-19 pandemic or fully ascertain its impact on the Company’s future results and market capitalization, which could adversely impact estimates such as the recoverability of goodwill and long-lived assets and the realizability of deferred tax assets. Actual results may ultimately differ from estimates, although management does not believe such differences would materially affect the financial statements in any individual year. Estimates and assumptions are periodically reviewed and the effects of revisions are reflected in the Consolidated Financial Statements in the period that they are determined. Cash and Cash Equivalents - Cash and cash equivalents include cash on hand, demand deposits, and temporary cash investments with original maturities less than three months. Allowance for Doubtful Accounts – The Company maintains allowances for estimated losses as a result of customers' inability to make required payments. Management evaluates the aging of the accounts receivable balances, the financial condition of its customers, historical trends, relevant forecasts, and the time outstanding of specific balances to estimate the amount of accounts receivable that may not be collected in the future and records the appropriate provision. Inventories – Inventories are stated at the lower of cost or net realizable value, determined on the first-in, first-out ("FIFO") basis. The value of inventory may decline as a result of surplus inventory, price reductions, or technological obsolescence. It is the Company’s policy to carry reserves against the carrying value of inventory when items have no future demand (obsolete inventory) and additionally, where inventory items on hand have demand, yet have insufficient forecasted activity to consume the entire stock within a reasonable period. The Company recognizes reserves against the carrying value of such at-risk inventory items after considering the nature of the risk and any mitigating factors. Property, Plant, and Equipment - Property, plant, and equipment includes the historic cost of land, buildings, equipment, and significant improvements to existing plant and equipment or, in the case of acquisitions, a fair market value appraisal of such assets completed at the time of acquisition. Property, plant, and equipment also includes the cost of purchased software. Expenditures for maintenance, repairs, and minor renewals are expensed as incurred. When property or equipment is sold or otherwise disposed of, the related cost and accumulated depreciation is removed from the respective accounts, and the gain or loss realized on disposition is reflected in earnings. The Company historically depreciates its assets on a straight-line basis over their estimated useful lives as follows: buildings and improvements 5 to 31.5 years; machinery and equipment 1.5 to 7 years; furniture and fixtures 2 to 5 years; vehicles 3 to 5 years; and software 3 to 5 years. Leases - The Company determines whether an arrangement is a lease at contract inception. Lease liabilities and right-of-use assets are recognized on the lease commencement date based on the net present value of fixed lease payments over the lease term. The Company includes options to extend or terminate a lease within the lease term when it is reasonably certain the option will be exercised. Leases with an initial term of 12 months or less are not recorded on the Consolidated Balance Sheets. Lease liabilities represent an obligation to make lease payments arising from a lease while right-of-use assets represent a right to use an underlying asset during the lease term. Right-of-use assets include prepaid fixed lease payments and exclude lease incentives. As the Company's leases do not have a readily determinable implicit rate, the Company uses its incremental borrowing rate to determine the present value of fixed lease payments based on information available at the lease commencement date. Fixed lease expense for operating leases and right-of-use asset amortization for finance leases are generally recognized on a straight-line basis over the lease term. Variable lease payments, such as payments based on an index rate or usage, are expensed as incurred and excluded from lease liabilities and right-of-use assets. The Company combines lease components and nonlease components such as maintenance into a single lease component, which results in the capitalization of all fixed payments within lease liabilities and right-of-use assets. Derivative Instruments - The Company uses derivative financial instruments to hedge its exposure to foreign currency exchange rate risk. The Company does not enter into derivative financial instruments for speculative purposes and does not have a material portfolio of derivative financial instruments. Derivative financial instruments used for hedging purposes must be designated and effective as a hedge of the identified risk exposure at inception of the contract. The Company recognizes all derivatives as either assets or liabilities on the Consolidated Balance Sheets and measures those instruments at fair value. For derivatives designated as cash flow hedges, the effective portion of changes in the fair value of the derivatives is recorded as a component of other comprehensive earnings and subsequently recognized in net earnings when the hedged items impact earnings. Goodwill and Indefinite-Lived Intangible Assets - Goodwill represents the excess of purchase consideration over the fair value of the net assets of businesses acquired. Goodwill and certain other intangible assets deemed to have indefinite lives are not amortized. Instead, goodwill and indefinite-lived intangible assets are tested for impairment at least annually, or more frequently if there are events or circumstances indicating the carrying value of individual reporting units or assets may exceed their respective fair values on a more likely than not basis. The Company performs its annual impairment assessment in the fourth quarter of each year on October 1. Recoverability of goodwill is measured at the reporting unit level. The Company has three reporting units. The goodwill balances associated with the Mobile Consumer Electronics ("MCE"), Hearing Health Technologies ("HHT"), and Precision Devices ("PD") reporting units were $741.0 million, $137.8 million, and $62.5 million, respectively, as of December 31, 2021. The impairment assessment compares the fair value of each reporting unit to its carrying value. Impairment is measured as the amount by which the carrying value of a reporting unit exceeds its fair value. Fair value is estimated using a discounted cash flow model that includes the Company’s market participant assumptions, forecasted future cash flows based on historical performance and future estimated results, determinations of appropriate discount rates, and other assumptions which are considered reasonable and inherent in the discounted cash flow analysis. Significant assumptions used in the assessment include forecasted revenue and terminal growth rates, profit margins, income taxes, and the Company's weighted average cost of capital. These assumptions require significant judgment and actual results may differ from estimated amounts. The fair value of all of the Company’s reporting units exceeded the carrying values by at least 35%, resulting in no goodwill impairment charges. Potential circumstances that could have a negative effect on the fair value of our reporting units include, but are not limited to, lower than forecasted growth rates or profit margins and changes in the weighted average cost of capital. A reduction in the estimated fair value of the reporting units could trigger an impairment in the future. The Company cannot predict the occurrence of certain events or changes in circumstances that might adversely affect the carrying value of goodwill and intangible assets. In testing its indefinite-lived trademarks for impairment, the Company uses a relief from royalty method to calculate and compare the fair value of the intangible asset to its carrying value. This method estimates the fair value of trademarks by calculating the present value of royalty income that could hypothetically be earned by licensing the trademark to a third party. Any excess of carrying value over the estimated fair value is recognized as an impairment loss. No impairment of indefinite-lived intangibles was indicated for the years ended December 31, 2021, 2020, or 2019. See Note 7. Goodwill and Other Intangible Assets for additional information on goodwill and indefinite-lived intangible assets. Other Intangible and Long-Lived Assets - Other intangible assets with determinable lives consist primarily of customer relationships, developed technology, and trademarks, which are amortized over estimated useful lives typically ranging from 5 to 10 years. There are no capitalized external legal costs incurred in the defense of patents as of December 31, 2021. Long-lived assets and intangible assets with determinable lives are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If an indicator of impairment exists for any grouping of assets, an estimate of undiscounted future cash flows is produced and compared to its carrying value. If an asset is determined to be impaired, the loss is measured by the excess of the carrying amount of the asset over its fair value as determined by an estimate of discounted future cash flows. The Company recorded impairment charges of $4.0 million and $7.6 million during the years ended December 31, 2021 and 2020, respectively. There were no impairments recorded during the year ended December 31, 2019. See Note 4. Impairments for additional details. Other Assets and Deferred Charges - Investments in mutual funds of $6.4 million and $2.5 million are included in Other assets and deferred charges as of December 31, 2021 and 2020, respectively. These investments are carried at fair value based on quoted prices for identical assets in active markets, resulting in classification within Level 1 of the fair value hierarchy. Gains and losses related to the investments are recorded within the Consolidated Statements of Earnings as a component of Other (income) expense, net. Other assets and deferred charges also include non-current deferred tax assets. Foreign Currency - Assets and liabilities of non-U.S. subsidiaries, where the functional currency is not the U.S. dollar, are translated into U.S. dollars at year-end exchange rates. Revenue and expense items are translated using weighted-average yearly exchange rates. Foreign currency translation gains and losses are included as a component of Accumulated other comprehensive loss. Assets and liabilities of an entity that are denominated in currencies other than an entity’s functional currency are re-measured into the functional currency using end of period exchange rates or historical rates where applicable to certain balances. Gains and losses related to these re-measurements are recorded within the Consolidated Statements of Earnings as a component of Other (income) expense, net. Revenue Recognition - Revenue is recognized when control of the promised goods or services is transferred to the customer in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The majority of the Company’s revenue is generated through the manufacture and sale of a broad range of specialized products and components. For product and component sales, each good sold to a customer typically represents a distinct performance obligation. The Company’s performance obligation to provide goods to a customer is typically satisfied at a point in time upon completion of the shipping process as indicated by the terms of the contract, at which point control is transferred to the customer and revenue is recognized. The Company has no significant arrangements with multiple performance obligations. Remaining performance obligations consist of the aggregate amount of the total transaction price that is unsatisfied or partially satisfied. As of December 31, 2021 and 2020, our total remaining performance obligations were immaterial. The Company recognizes sales-based royalty revenue under third-party license agreements as the related sales are made by licensees. The terms of a contract or historical business practice can give rise to variable consideration, including customer discounts, rebates, and returns. The Company estimates variable consideration using either the expected value or most likely amount method. We include amounts in the transaction price to the extent it is probable that a significant reversal of revenue will not occur in a subsequent reporting period. Our estimates of variable consideration are based on all reasonably available information (historical, current, and forecasted). Rebates are recognized over the contract period based on expected revenue levels. Sales discounts and rebates totaled $5.0 million, $4.2 million, and $4.7 million for the years ended December 31, 2021, 2020, and 2019, respectively. Returns and allowances totaled $4.3 million, $5.4 million, and $6.6 million for the years ended December 31, 2021, 2020, and 2019, respectively. The Company accounts for shipping and handling activities that occur after control of the related good transfers to the customer as fulfillment activities rather than evaluating such activities as performance obligations. As a result, all shipping and handling costs related to contracts with customers are recognized in the Cost of goods sold line on the Consolidated Statements of Earnings. Additionally, the Company applies the practical expedient allowing incremental costs of obtaining a contract to be expensed as incurred if the amortization period of the resulting asset would have been less than one year. These costs primarily consist of sales commissions and the Company has no such significant costs exceeding the one year limit for applying the practical expedient. Receivables, net from contracts with customers were $137.7 million and $123.8 million as of December 31, 2021 and 2020, respectively. See Note 18. Segment Information for disclosures regarding the disaggregation of revenues. Stock-Based Compensation – The principal awards issued under the stock-based compensation plans include stock options, restricted stock units ("RSUs"), and performance share units ("PSUs"). The cost for such awards is measured at the grant date based on the fair value of the award. The value of the portion of the award that is expected to ultimately vest is generally recognized as expense on a straight-line basis, generally over the explicit service period and is included in Cost of goods sold, Research and development expenses, and Selling and administrative expenses in the Consolidated Statements of Earnings, depending on the functional area of the underlying employees. At the time of grant, the Company estimates forfeitures, based on historical experience, in order to estimate the portion of the award that will ultimately vest. The Company uses the Black-Scholes valuation model to estimate the fair value of stock options granted to employees. The fair value of each RSU granted is equal to the share price at the date of the grant. The fair value of each PSU is determined using a Monte Carlo simulation. The cost related to PSUs with performance conditions is recognized based on the expected attainment of performance targets. Changes in estimates for performance conditions that impact the number of shares expected to vest are recognized prospectively through cumulative adjustments. The cost for PSUs is recognized regardless of the expected attainment of market conditions as the grant date fair value considers the range of possible stock price and total shareholder return outcomes. See Note 14. Equity Incentive Program for additional information related to the Company’s stock-based compensation. Income Taxes - The Company records a provision for income taxes for the anticipated tax consequences of the reported results of operations using the asset and liability method. Under this method, the Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. The Company offsets and presents deferred tax liabilities and assets, as well as any related valuation allowance, as a single non-current amount on the Consolidated Balance Sheets on a jurisdictional basis. The Company's policy is to release income tax effects from accumulated other comprehensive loss in the period the underlying item expires. The Company establishes valuation allowances for its deferred tax assets if, based on all available positive and negative evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. In making such assessments, significant weight is given to evidence that can be objectively verified. The assessment of the need for a valuation allowance requires considerable judgment on the part of management with respect to the benefits that could be realized from future taxable income, as well as other positive and negative factors. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income, and tax-planning strategies in making this assessment. The Company recognizes tax benefits from uncertain tax positions only if it believes that it is more likely than not that the tax position will be sustained on examination by the taxing authorities based on the technical merits of the position. Adjustments are made to these reserves when facts and circumstances change, such as the closing of a tax audit or the refinement of an estimate. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on the Company's financial condition and operating results. The provision for income taxes includes the effects of any reserves that are believed to be appropriate, as well as the related net interest and penalties. Research and Development Costs – Research and development costs, including qualifying engineering costs, are expensed when incurred. Non-cash Investing Activities - Purchases of property, plant, and equipment included in accounts payable at December 31, 2021, 2020, and 2019 were $5.4 million, $2.0 million, and $4.7 million, respectively. These non-cash amounts are not reflected as Capital expenditures within investing activities of the Consolidated Statements of Cash Flows for the respective periods. Recently Issued Accounting Standards In August 2020, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2020-06 to simplify the accounting for certain financial instruments with characteristics of liabilities and equity. The standard eliminates certain accounting models that separated embedded conversion features from host contracts for convertible instruments, requiring bifurcation only if the convertible feature qualifies as a derivative under Accounting Standards Codification ("ASC") 815 or for convertible instruments issued at a substantial premium. In addition, the guidance requires the if-converted method of calculating diluted earnings per share for convertible instruments, which eliminates the use of the treasury stock method for instruments that may be settled in cash or shares. The standard is effective for public business entities for fiscal years beginning after December 15, 2021, including interim periods within those fiscal years. The standard can be adopted on a modified retrospective basis to transactions outstanding as of the adoption date or on a fully retrospective basis to all periods presented. The Company will adopt the standard using the modified retrospective method on January 1, 2022. The Company does not expect the standard to impact the Consolidated Financial Statements as all of its convertible instruments matured prior to the adoption date. See Note 12. Borrowings for detail on the Company's convertible instruments.

Disposed and Discontinued Opera

Disposed and Discontinued Operations (Notes)	12 Months Ended
	Dec. 31, 2021
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations, Disclosure	Management and the Board of Directors periodically conduct strategic reviews of the Company's businesses. On November 28, 2017, the Company completed the sale of its high-end oscillators business (“Timing Device Business”), part of the Precision Devices (“PD”) segment, for $130.0 million, plus purchase price adjustments for a net amount of $135.1 million. On July 7, 2016, the Company completed the sale of its speaker and receiver product line (“Speaker and Receiver Product Line”) for $45.0 million in cash, less purchase price adjustments for a net amount received of $40.6 million. In accordance with ASC 205-20, Presentation of Financial Statements – Discontinued Operations, the results of operations and financial positions of the Timing Device Business and Speaker and Receiver Product Line have been reclassified to discontinued operations for all periods presented as these disposals represent strategic shifts that had a major effect on the Company's results of operations. Summarized results of the Company's discontinued operations are as follows: Years Ended December 31, (in millions) 2021 2020 2019 Revenues $ — $ — $ — Operating income — — — Earnings from discontinued operations before taxes — — — (Benefit from) provision for income taxes (1) (0.2) (3.7) 0.6 Earnings (loss) from discontinued operations, net of tax $ 0.2 $ 3.7 $ (0.6) (1) The Company recorded a tax benefit for a refund received during the first quarter of 2020 related to the Timing Device Business. Assets and liabilities of discontinued operations are summarized below: (in millions) December 31, 2020 Liabilities of discontinued operations: Other liabilities (1) $ 0.6 Total liabilities $ 0.6 (1) This accrual was attributable to an unrecognized tax benefit recorded during the fourth quarter of 2019 related to the Speaker and Receiver Product Line.

Acquisition Acquisition

Acquisition Acquisition	12 Months Ended
	Dec. 31, 2021
Business Combinations [Abstract]
Business Acquisition, Integration, Restructuring and Other Related Costs	ASIC Design Business On December 20, 2019, the Company acquired substantially all of the assets of the ASIC Design Business from ams AG for $57.9 million. The acquired business, which does not generate revenues, includes intellectual property and an assembled workforce. The transaction was accounted for under the acquisition method of accounting and the results of operations are included in the Consolidated Financial Statements from the date of acquisition in the Audio segment. Included in the Consolidated Statements of Earnings is a loss before income taxes of $0.1 million from the date of acquisition through December 31, 2019. Unaudited Pro-forma Summary The following unaudited pro-forma summary presents consolidated financial information as if the ASIC Design Business had been acquired on January 1, 2018. The unaudited pro-forma financial information is based on historical results of operations and financial positions of the Company and the ASIC Design Business. The pro-forma results include estimated amortization of definite-lived intangible assets and exclude cost savings and transaction costs. The unaudited pro-forma financial information does not necessarily represent the results that would have occurred had the acquisition occurred on January 1, 2018. In addition, the unaudited pro-forma information should not be deemed to be indicative of future results. (unaudited) (in millions, except per share amounts) Year Ended December 31, 2019 Earnings from continuing operations: As reported $ 49.7 Pro-forma 40.7 Basic earnings per share from continuing operations: As reported $ 0.55 Pro-forma 0.45 Diluted earnings per share from continuing operations: As reported $ 0.53 Pro-forma 0.44 Other Acquisitions On January 3, 2019, the Company acquired substantially all of the assets of DITF for $11.1 million. The acquired business provides thin film components to the defense, telecommunication, industrial, and medtech markets. The transaction was accounted for under the acquisition method of accounting and the results of operations are included in the Consolidated Financial Statements from the date of acquisition in the PD segment. Included in the Consolidated Statements of Earnings are DITF's revenues and earnings before income taxes of $8.9 million and $0.3 million, respectively, from the date of acquisition through December 31, 2019. Pro-forma financial information has not been provided as the acquisition did not have a material impact on the Consolidated Statements of Earnings. On January 19, 2018, the Company acquired substantially all of the assets of Compex Corporation for $16.0 million, plus purchase price adjustments for a net amount of $18.7 million. The asset purchase agreement relating to the acquisition provided for a $1.0 million holdback that was paid during the third quarter of 2019. The acquired business provides single layer electronic components to the telecommunication, fiber optics, and defense markets. The transaction was accounted for under the acquisition method of accounting and the results of operations are included in the Consolidated Financial Statements from the date of acquisition in the PD segment.

Inventories

Inventories	12 Months Ended
	Dec. 31, 2021
Inventory, Net [Abstract]
Inventories, net	5. Inventories, net The following table details the major components of inventories, net: (in millions) December 31, 2021 December 31, 2020 Raw materials $ 89.6 $ 89.7 Work in progress 33.6 31.0 Finished goods 66.7 48.4 Subtotal 189.9 169.1 Less reserves (36.8) (39.0) Total $ 153.1 $ 130.1

Property, Plant and Equipment,

Property, Plant and Equipment, net	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, net	6. Property, Plant, and Equipment, net The following table details the major components of property, plant, and equipment, net: (in millions) December 31, 2021 December 31, 2020 Land $ 12.9 $ 8.0 Buildings and improvements 119.3 111.9 Machinery, equipment, and other 575.0 562.8 Subtotal 707.2 682.7 Less accumulated depreciation (506.4) (491.2) Total $ 200.8 $ 191.5

Accrued Expenses and Other Liab

Accrued Expenses and Other Liabilities	12 Months Ended
	Dec. 31, 2021
Accrued Liabilities and Other Liabilities [Abstract]
Accrued Expenses and Other Liabilities	9. Other Accrued Expenses and Other Liabilities The following table details the major components of other accrued expenses: (in millions) December 31, 2021 December 31, 2020 Sales volume rebates $ 4.9 $ 3.5 Accrued taxes other than income taxes 4.2 3.7 Current finance lease liabilities 2.7 2.6 Accrued insurance 1.7 1.7 Warranty 0.5 0.4 Restructuring and exit costs 0.4 2.4 Hedging liability 0.2 — Other 4.8 4.3 Total $ 19.4 $ 18.6 The following table details the major components of other liabilities: (in millions) December 31, 2021 December 31, 2020 Deferred compensation, including defined benefit plans $ 13.9 $ 20.5 Long-term finance lease liabilities 3.6 5.5 Unrecognized tax benefits 2.0 1.5 Restructuring and exit costs — 0.2 Other (1) 1.1 5.1 Total $ 20.6 $ 32.8 (1) Balance at December 31, 2020 included an accrual for the estimated loss of $2.2 million related to the leased facility in Santa Clara, California. See Note 4. Impairments for additional details. Warranty Accruals Estimated warranty program claims are provided for at the time of sale. Amounts provided for are based on historical costs and adjusted for new claims. The changes in the carrying amount of product warranties were as follows: Years Ended December 31, (in millions) 2021 2020 2019 Beginning balance, January 1 $ 0.4 $ 0.9 $ 0.5 Provision for warranties 1.0 3.8 3.8 Settlements made (0.9) (4.3) (3.4) Ending balance, December 31 $ 0.5 $ 0.4 $ 0.9

Restructuring and Related Activ

Restructuring and Related Activities	12 Months Ended
	Dec. 31, 2021
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities	10. Restructuring and Related Activities Restructuring and related activities are designed to better align the Company's operations with current market conditions through targeted facility consolidations, headcount reductions, and other measures to further optimize operations. No restructuring charges were recorded within Gross profit for the year ended December 31, 2021. During the year ended December 31, 2021, the Company recorded restructuring charges within Operating expenses of $0.5 million. These charges were primarily for actions associated with the Intelligent Audio product line, which is included within the Audio segment. During the year ended December 31, 2020, the Company restructured its Intelligent Audio product line. These actions resulted in a reduction in workforce and the refocusing of certain research and development activities. The Company recorded restructuring charges of $8.3 million related to these actions, including $5.4 million in severance pay and benefits, $1.7 million in fixed asset write-off costs, and $1.2 million in contract termination costs. In addition, during the year ended December 31, 2020, the Company recorded restructuring charges of $4.0 million for severance pay and benefits primarily to rationalize the remaining Audio segment workforce as a direct result of the lower demand the Company experienced due to the COVID-19 pandemic. During the year ended December 31, 2020, the Company recorded total restructuring charges within Gross profit of $2.3 million, primarily for fixed asset write-off costs and severance pay and benefits associated with the restructuring of the Intelligent Audio product line and other actions to rationalize the remaining Audio segment workforce. The Company also recorded total restructuring charges within Operating expenses of $10.0 million, primarily for severance pay and benefits and contract termination costs associated with the restructuring of the Intelligent Audio product line and other actions to rationalize the remaining Audio segment workforce. During the year ended December 31, 2019, the Company recorded restructuring charges of $1.7 million within Gross profit, primarily for actions associated with transferring certain operations of capacitors manufacturing to other existing facilities in order to further optimize operations in the PD segment, as well as rationalizing the Audio segment workforce. The Company also recorded restructuring charges of $4.3 million within Operating expenses, primarily for actions associated with rationalizing the Audio segment workforce. The following table details restructuring charges incurred by reportable segment for the periods presented: Years Ended December 31, (in millions) 2021 2020 2019 Audio $ 0.4 $ 10.5 $ 4.8 Precision Devices 0.1 0.1 0.8 Corporate — 1.7 0.4 Total $ 0.5 $ 12.3 $ 6.0 The following table details the Company’s severance and other restructuring accrual activity: (in millions) Severance Pay and Benefits Contract Termination and Other Costs Total Balance at January 1, 2019 $ 0.8 $ — $ 0.8 Restructuring charges 6.0 — 6.0 Payments (5.4) — (5.4) Balance at December 31, 2019 1.4 — 1.4 Restructuring charges 9.4 1.2 10.6 Payments (8.9) (0.5) (9.4) Balance at December 31, 2020 1.9 0.7 2.6 Restructuring charges 0.5 — 0.5 Payments (2.0) (0.7) (2.7) Balance at December 31, 2021 $ 0.4 $ — $ 0.4 The severance and restructuring accruals are recorded in the following line items on the Consolidated Balance Sheets: (in millions) December 31, 2021 December 31, 2020 Other accrued expenses $ 0.4 $ 2.4 Other liabilities — 0.2 Total $ 0.4 $ 2.6

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	13. Income Taxes The components of earnings before income taxes and discontinued operations were: Years Ended December 31, (in millions) 2021 2020 2019 Domestic $ 15.5 $ (26.2) $ (48.3) Foreign 89.1 37.5 114.6 Total earnings before income taxes and discontinued operations $ 104.6 $ 11.3 $ 66.3 Income tax (benefit) expense for the years ended December 31, 2021, 2020, and 2019 is comprised of the following: Years Ended December 31, (in millions) 2021 2020 2019 Current: U.S. Federal $ 0.4 $ 0.7 $ 0.7 State and local 0.3 0.2 0.2 Foreign 14.8 10.3 15.9 Total current tax expense $ 15.5 $ 11.2 $ 16.8 Deferred: U.S. Federal $ (57.1) $ (0.4) $ 0.1 State and local (2.6) 0.2 (0.1) Foreign (1.4) (2.6) (0.2) Total deferred tax benefit (61.1) (2.8) (0.2) Total income tax (benefit) expense $ (45.6) $ 8.4 $ 16.6 The reconciliation of the U.S. Federal income tax rate to the Company’s effective income tax rate was as follows: Years Ended December 31, 2021 2020 2019 U.S. Federal income tax rate 21.0 % 21.0 % 21.0 % State and local taxes, net of Federal income tax benefit 0.3 % 4.2 % 0.2 % Foreign operations tax effect 3.3 % 17.3 % 5.0 % Research and experimentation tax credits (3.8) % (29.5) % (5.0) % Valuation allowance (57.1) % 85.4 % 15.0 % Tax contingencies 0.6 % 0.3 % 1.3 % Tax holiday (10.1) % (37.8) % (24.6) % Foreign taxes 1.0 % 2.8 % 2.1 % Non-deductible and non-taxable interest (0.2) % 1.0 % (2.9) % Stock-based compensation 4.8 % 11.3 % 3.0 % Other, principally non-tax deductible items 0.1 % 1.1 % 0.3 % Global low tax and foreign derived intangible income (2.3) % 12.1 % 10.6 % Foreign currency adjustments (0.7) % (6.1) % — % Prior period items (0.5) % (8.8) % (1.0) % Effective income tax rate (43.6) % 74.3 % 25.0 % The Company’s effective tax rate is favorably impacted by two tax holidays granted to us by Malaysia, one of which is effective through December 31, 2026 and the other of which expired on July 31, 2021. These tax holidays are subject to the Company ’s annual sat isfaction of certain conditions, including investment and sales thresholds, which the Company expects to maintain. The remaining Malaysian tax holiday, which was extended during the fourth quarter of 2021, reduces the anticipated effective rate on qualified income to approximately 7.2% versus the statutory rate of 24.0%, through 2026. If the Company fails to satisfy such conditions, the Company’s effective tax rate may be significantly adversely impacted. The continuing operations benefit of these incentives for the years ending December 31, 2021, 2020, and 2019 is estimated to be $10.7 million, $3.8 million, and $14.6 million, respectively. The continuing operations benefit of the tax holidays on a basic per share basis for the years ending December 31, 2021, 2020, and 2019 was $0.12 , $0.04, and $0.16, respectively. The components of the Company’s deferred tax assets and liabilities included the following: (in millions) December 31, 2021 December 31, 2020 Deferred tax assets: Accrued compensation, principally post-retirement, and other employee benefits $ 10.4 $ 14.1 Accrued expenses, principally for state income taxes and warranty 6.1 8.6 Accrued interest 5.9 7.7 Net operating loss and other carryforwards 70.9 71.6 Inventories, principally due to reserves for financial reporting purposes and capitalization for tax purposes 7.7 6.5 Convertible note hedges — 1.8 Unremitted earnings of non-U.S. subsidiaries 1.6 — Intangible assets, principally due to different tax and financial reporting bases 0.6 — Plant and equipment, principally due to differences in depreciation 17.0 13.0 Total gross deferred tax assets 120.2 123.3 Valuation allowance (39.1) (98.0) Total deferred tax assets $ 81.1 $ 25.3 Deferred tax liabilities: Intangible assets, principally due to different tax and financial reporting bases $ — $ (4.3) Debt discount on convertible notes — (1.4) Unremitted earnings of non-U.S. subsidiaries — (0.9) Other liabilities (3.0) (0.8) Total gross deferred tax liabilities (3.0) (7.4) Net deferred tax asset $ 78.1 $ 17.9 Classified as follows in the Consolidated Balance Sheets: Other assets and deferred charges (non-current deferred tax assets) $ 78.7 $ 19.9 Deferred income taxes (non-current deferred tax liabilities) (0.6) (2.0) Net deferred tax asset $ 78.1 $ 17.9 A reduction of the carrying amounts of deferred tax assets by a valuation allowance is required if, based on all available evidence, it is more likely than not that such assets will not be realized. The need to establish valuation allowances for deferred tax assets is assessed at each reporting period. In assessing the requirement for, and amount of, a valuation allowance in accordance with the more-likely-than-not standard, the Company gives appropriate consideration to all positive and negative evidence related to the realization of the deferred tax assets. This assessment considers, among other matters, the nature, frequency, and severity of current and cumulative losses, forecasts of future profitability, the duration of statutory carryforward periods, the Company's experience with operating loss and tax credit carryforwards not expiring unused, and tax planning strategies. In determining the need for the valuation allowance, the Company considered all positive and negative evidence. The Company gives more weight to evidence that is objective in nature as compared to subjective evidence. Significant weight is given to evidence that directly relates to current financial performance. During the year ended December 31, 2021, the Company emerged from a three-year U.S. cumulative loss position. Recent domestic pre-tax operating earnings is a significant, principal piece of positive evidence. Other positive evidence included strategic actions taken by the Company to lower costs specific to U.S. operations. As a result, the Company determined that a significant portion of the U.S. valuation allowance should be reversed. During the year ended December 31, 2021, the Company recorded a decrease in the U.S. valuation allowance of $59.1 million. As of December 31, 2021, the Company's net deferred tax assets of $78.1 million included a valuation allowance of $39.1 million against certain state, federal, and foreign deferred tax assets. At December 31, 2021, the Company had $20.6 million of U.S. fe deral net operating losses that are available, of which $7.3 million will expire in the next 5 to 10 years, and of which $13.3 million will expire in the next 11 to 20 years. There are $49.5 million of domestic State net operating losses that are available between 2027 and 2040. There are $14.3 million of non-U.S. net operating loss carryforwards, of which $0.1 million will expire in the next 5 years; $1.4 million will expire in the next 5 to 10 years; $9.4 million will expire in the next 10 to 20 years; $2.8 million can be carried forward indefinitely; and $0.6 million is capital loss carried forward indefinitely. The Company has $26.8 million of U.S. federal research and development credits that begin to expire in 2022 and $16.4 million of foreign tax credits that begin to expire in 2027. In addition, the Company has $20.4 million of state credits, of which $2.9 million will expire between 2022 and 2036 if unused, and $17.5 million can be carried forward indefinitely. The Company has not provided for U.S. federal income taxes on the historical undistributed earnings of its international subsidiaries because such earnings are currently reinvested in foreign jurisdictions and will continue to be reinvested indefinitely, with the exception of its Malaysian and Luxembourg subsidiaries. Our Malaysian principal subsidiary is our primary source of foreign earnings and cash. Any future decision to distribute cash from this subsidiary to the U.S. should not result in a material amount of U.S. or foreign taxes as the majority of the Company's $1.1 billion historical undistributed earnings have been previously taxed in the U.S. under the Tax Cuts and Jobs Act of 2017. Unrecognized Tax Benefits The Company records interest and penalties associated with unrecognized tax benefits as a component of income tax expense. During the years ended December 31, 2021, 2020, and 2019, the Company recorded no potential interest benefit or expense. There was no accrued interest at December 31, 2021, 2020 and 2019. There was no recorded potential penalty expense during the years ended December 31, 2021, 2020, and 2019. Total accrued penalties at December 31, 2021, 2020, and 2019 of $0.3 million were included in Other liabilities on the Consolidated Balance Sheets. The Company's tax returns are routinely audited by the tax authorities in the relevant jurisdictions. For tax years before 2017, the Company is no longer subject to U.S. federal income tax examination. For tax years before 2015, the Company’s Malaysian principal subsidiary is no longer subject to examination. Included in the balance of total unrecognized tax benefits at December 31, 2021 are potential benefits of $2.0 million, which if recognized, would affect the effective rate on earnings from continuing operations. Given the Company's current valuation allowance position, no benefit is expected to result from the reversal of any uncertain tax position associated with the acquired attributes. Unrecognized tax benefits at January 1, 2019 $ 10.1 Additions for tax positions of prior years 2.8 Reductions for tax positions of prior years (0.1) Settlements (0.1) Unrecognized tax benefits at December 31, 2019 $ 12.7 Settlements (2.6) Foreign exchange fluctuations 0.1 Unrecognized tax benefits at December 31, 2020 $ 10.2 Reductions for tax positions of prior years (0.3) Settlements (0.4) Unrecognized tax benefits at December 31, 2021 $ 9.5

Equity Incentive Program

Equity Incentive Program	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Performance Shares, Outstanding Activity [Table Text Block]	14. Equity Incentive Program The Company maintains equity compensation plans that provide for the issuance of Knowles stock to directors, executive officers, and other employees. The maximum number of shares available for issuance under the plans is 16.1 million, of which 11.0 million were available for future awards at December 31, 2021. The following table summarizes the stock-based compensation expense recognized by the Company for the periods presented: Years Ended December 31, (in millions) 2021 2020 2019 Pre-tax stock-based compensation expense Cost of goods sold $ 1.6 $ 1.7 $ 1.5 Research and development expenses 5.5 6.2 7.7 Selling and administrative expenses 25.0 9.4 16.0 Total pre-tax stock-based compensation expense 32.1 17.3 25.2 Tax benefit 5.1 — — Total stock-based compensation expense, net of tax $ 27.0 $ 17.3 $ 25.2 Compensation expense for stock-based awards is measured based on the fair value of the awards as of the date the stock-based awards are granted and adjusted to the estimated number of awards that are expected to vest. Forfeitures are estimated based on historical experience at the time of grant and revised in subsequent periods if actual forfeitures differ from those estimates. Compensation costs for stock-based awards are amortized over their service period. Stock Option s and SSARs The fair value of stock options granted by the Company was estimated on the date of grant using a Black-Scholes option-pricing model based on the assumptions shown in the table below. Years Ended December 31, 2021 2020 2019 Risk-free interest rate 0.06% 0.11% to 1.42% 1.55% to 2.44% Dividend yield —% —% —% Expected life (years) 4.5 4.3 to 4.5 4.5 Volatility 36.0% 38.8% to 40.6% 40.0% to 42.9% Fair value at date of grant $6.14 to $6.31 $4.78 to $5.95 $6.22 to $7.45 Expected volatilities are based on the historical volatility of the Company’s stock. The risk-free interest rate is based on U.S. government issues with a remaining term equal to the expected life of the stock options. The expected term is the period over which our employees are expected to hold their options. It is based on the simplified method from the SEC’s safe harbor guidelines. The Company does not currently anticipate paying dividends over the expected term. The exercise price per share for the stock options granted by the Company was equal to the closing price of Knowles' stock on the NYSE on the date of the grant. The period during which options granted by the Company were exercisable was fixed by Knowles' Compensation Committee of the Board of Directors at the time of grant. Generally, stock options vest one-third on each of the first three anniversaries of the grant date and expire 7 years from the grant date. The following table summarizes the Company's stock-settled stock appreciation right ("SSAR") and stock option activity for the year ended December 31, 2021. SSARs Stock Options Number of Shares Weighted-Average Exercise Price Aggregate Intrinsic Value Weighted-Average Remaining Contractual Term (Years) Number of Shares Weighted-Average Exercise Price Aggregate Intrinsic Value Weighted-Average Remaining Contractual Term (Years) (in millions, except share and per share amounts) Outstanding at December 31, 2020 596,537 $ 22.72 5,765,903 $ 17.44 Granted — — 220,963 20.61 Exercised (114,096) 21.77 (1,540,314) 16.64 Forfeited — — (119,662) 17.35 Expired (106,477) 22.17 (848,452) 29.52 Outstanding at December 31, 2021 375,964 $ 23.16 $ 0.2 0.8 3,478,438 $ 15.04 $ 28.9 3.1 Exercisable at December 31, 2021 375,964 $ 23.16 $ 0.2 0.8 2,645,456 $ 14.25 $ 24.1 2.4 The aggregate intrinsic value in the table above represents the difference between the Company's closing stock price on December 31, 2021 and the exercise price of each SSAR and stock option, multiplied by the number of in-the-money awards. There was no unrecognized compensation expense related to SSARs at December 31, 2021. Unrecognized compensation expense related to stock options not yet exercisable at December 31, 2021 was $2.5 million. This cost is expected to be recognized over a weighted-average period of 1.1 years. Other information regarding the exercise of SSARs and stock options is listed below: Years Ended December 31, (in millions) 2021 2020 2019 SSARs Aggregate intrinsic value of SSARs exercised $ 0.1 $ — $ 0.4 Stock Options Cash received by Knowles for exercise of stock options $ 25.6 $ 1.8 $ 9.8 Aggregate intrinsic value of stock options exercised 6.6 0.4 2.7 Tax benefit from stock options exercised 1.2 — — RSUs The following table summarizes the Company's RSU activity for the year ended December 31, 2021: Share units Weighted-average grant date fair value Unvested at December 31, 2020 1,909,786 $ 16.14 Granted 1,159,374 20.59 Vested (1) (1,068,104) 15.81 Forfeited (222,417) 18.42 Unvested at December 31, 2021 1,778,639 $ 18.89 (1) The number of RSUs vested includes shares that the Company withheld on behalf of employees to satisfy statutory tax withholding requirements. RSUs vest based on the passage of time. Generally, RSUs have a three year vesting schedule and vest one-third on each of the first three anniversaries of the grant date. The fair value of RSUs vested during the year ended December 31, 2021 was $21.9 million. At December 31, 2021, $19.7 million of unrecognized compensation expense related to RSUs is expected to be recognized over a weighted-average period of 1.6 years. PSUs The Company grants PSUs to senior management. In each case, the awards will cliff vest three years following the grant date. PSUs will be settled in shares of the Company's common stock. Depending on the Company's overall performance relative to the applicable measures, the size of the PSU awards are subject to adjustment, up or down, resulting in awards at the end of the performance period that can range from 0% to 225% of target. The Company will ratably recognize the expense over the applicable service period for each grant of PSUs and adjust the expense for the expected achievement of performance conditions as appropriate. The fair value of PSUs is determined by using a Monte Carlo simulation. For the awards granted in February 2021, the number of PSUs that may be earned and vest is based on total shareholder return (“TSR”) relative to the component companies of the Russell 2000 Index over a three-year performance period. The COVID-19 pandemic brought on unique and unprecedented challenges to the Company, particularly in the hearing health and medtech markets. Many of the Company's executive compensation programs were affected, including outstanding PSU awards. Due to the impact of the COVID-19 pandemic on the Company’s overall business performance, effective February 8, 2021, the Company’s Compensation Committee approved certain modifications to PSUs granted in February 2018, 2019, and 2020. For the awards granted in February 2018 (the “2018 PSUs”), the number of PSUs that may be earned and vest was originally based on the Company’s revenues and stock price performance over a three-year performance period. The modified award was based on the Company’s revenues and stock price performance over three separate one-year performance periods to isolate the impact of the COVID-19 pandemic on the Company's fiscal 2020 performance. In addition, the performance periods corresponding to fiscal 2018 and 2019 were weighted at 25% each while the performance period corresponding to fiscal 2020 was weighted at 50%, given the impact of fiscal 2020 performance on shareholders. Service conditions were not modified. The modification of the 2018 PSUs affected nine employees and resulted in total incremental compensation expense of $3.9 million, which was recognized in the first quarter of 2021 as there was no remaining service period. In February 2021, the 2018 PSUs were converted from 329,092 PSUs to 190,544 shares of common stock based on achievement of the modified conditions. For the awards granted in February 2019 (the “2019 PSUs”), the number of PSUs that may be earned and vest was originally based on the Company's revenues and TSR relative to the component companies of the S&P Semiconductor Select Industry Index over a three-year performance period. The modified award is based on the Company’s revenues and TSR relative to the component companies of the S&P Semiconductor Select Industry Index over three separate one-year performance periods to isolate the impact of the COVID-19 pandemic on the Company's fiscal 2020 performance. Each period is weighted equally, as the Company expected to face challenges related to the COVID-19 pandemic in fiscal 2021. Service conditions were not modified. The modification of the 2019 PSUs affected eight employees and resulted in total incremental compensation expense of $2.4 million, which will be recognized over the remaining service period. Incremental compensation expense was subject to adjustment for the achievement of the performance condition based on fiscal 2021 revenues. For the awards granted in February 2020 (the “2020 PSUs”), the number of PSUs that may be earned and vest was originally based on TSR relative to the component companies of the S&P Semiconductor Select Industry Index over a three-year performance period. The modified award replaces the S&P Semiconductor Select Industry Index with the Russell 2000 Index. The Company is a member of the Russell 2000 Index, which represents a broader, more diversified index that better aligns with the Company's strategy. Service conditions were not modified. The modification of the 2020 PSUs affected eight employees and resulted in total incremental compensation expense of $4.7 million, which will be recognized over the remaining service period. The following table summarizes the Company's PSU activity for the year ended December 31, 2021: Share units Weighted-average grant date fair value Unvested at December 31, 2020 920,973 $ 16.04 Granted 293,874 28.49 Vested (1) (346,898) 14.13 Forfeited (101,483) 19.05 Unvested at December 31, 2021 766,466 $ 21.28 (1) The number of PSUs vested includes shares that the Company withheld on behalf of employees to satisfy statutory tax withholding requirements. The fair value of PSUs vested during the year ended December 31, 2021 was $3.9 million. At December 31, 2021, $10.0 million of unrecognized compensation expense related to PSUs is expected to be recognized over a weighted-average period of 1.2 years.

Commitments and Contingent Liab

Commitments and Contingent Liabilities	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingent Liabilities	15. Commitments and Contingent Liabilities From time to time, the Company is involved in various legal proceedings and claims arising in the ordinary course of its business. The majority of these claims and proceedings relate to commercial, warranty, employment, and intellectual property matters. Although the ultimate outcome of any legal proceeding or claim cannot be predicted with certainty, based on present information, including management’s assessment of the merits of the particular claim, the Company believes that the disposition of these legal proceedings or claims, individually or in the aggregate, after taking into account recorded accruals and the availability and limits of insurance coverage, will not have a material adverse effect on its cash flow, results of operations, or financial condition. The Company owns many patents and other intellectual property pertaining to its products, technology, and manufacturing processes. Some of the Company's patents have been and may continue to be infringed upon or challenged by others. In appropriate cases, the Company has taken and will take steps to protect and defend its patents and other intellectual property, including through the use of legal proceedings in various jurisdictions around the world. Such steps have resulted in and may continue to result in retaliatory legal proceedings, including litigation or other legal proceedings in various jurisdictions and forums around the world alleging infringement by the Company of patents owned by others. The costs of investigations and legal proceedings relating to the enforcement and defense of the Company’s intellectual property may be substantial. Additionally, in multi-forum disputes, the Company may incur adverse judgments with regard to certain claims in certain jurisdictions and forums while still contesting other related claims against the same opposing party in other jurisdictions and forums. Intellectual Property Infringement Claims The Company may, on a limited customer specific basis, provide contractual indemnities for certain losses that arise out of claims that its products infringe on the intellectual property of others. It is not possible to determine the maximum potential amount under these indemnification agreements due to the unique facts and circumstances involved in each particular agreement. Historically, the Company has not made significant payments under such indemnity arrangements. The Company’s legal accruals associated with these indemnity arrangements were not significant at December 31, 2021 and 2020.

Employee Benefit Plans (Notes)

Employee Benefit Plans (Notes)	12 Months Ended
	Dec. 31, 2021
Retirement Benefits [Abstract]
Employee Benefit Plans	16. Employee Benefit Plans Knowles sponsors its own defined contribution plans. The Company's expense relating to defined contribution plans was $6.2 million, $6.2 million, and $7.2 million for the years ended December 31, 2021, 2020, and 2019, respectively. Knowles sponsors four defined benefit pension plans to certain non-U.S. employees. The two plans in the U.K. and the plan in Taiwan are closed to new participants; however, all active participants in these plans continue to accrue benefits. The plan in the Philippines is open to new participants. These plans are considered direct obligations of the Company and have been recorded within the accompanying Consolidated Financial Statements. Non-U.S. Defined Benefit Pension Plans Obligations and Funded Status The following tables summarize the balance sheet impact, including the benefit obligations, assets, and funded status associated with the Company's four defined benefit plans for non-U.S. participants at December 31, 2021 and 2020. December 31, (in millions) 2021 2020 Change in benefit obligation: Benefit obligation at beginning of year $ 74.5 $ 64.1 Service cost 0.3 0.3 Interest cost 0.9 1.2 Benefits paid (1.6) (1.7) Actuarial (gain) loss (1) (3.8) 8.3 Settlements and curtailments — (0.2) Currency translation and other (0.8) 2.5 Benefit obligation at end of year 69.5 74.5 Change in plan assets: Fair value of plan assets at beginning of year 65.7 58.2 Actual return on plan assets 4.6 5.8 Company contributions 1.5 1.5 Benefits paid (1.6) (1.7) Settlements and curtailments — (0.2) Currency translation and other (0.9) 2.1 Fair value of plan assets at end of year 69.3 65.7 Funded status $ (0.2) $ (8.8) Amounts recognized in the Consolidated Balance Sheets consist of: Other assets and deferred charges $ 2.6 $ — Other liabilities (2.8) (8.8) Funded status $ (0.2) $ (8.8) Accumulated other comprehensive loss: Net actuarial losses $ 19.2 $ 25.6 Prior service cost 1.1 1.1 Deferred taxes (3.3) (4.8) Total accumulated other comprehensive loss, net of tax 17.0 21.9 Accumulated benefit obligation $ 68.4 $ 73.3 (1) The net actuarial gains and losses during the years ended December 31, 2021 and 2020 primarily related to changes in the discount rates for the U.K. plans. Pension plans with projected benefit obligations in excess of plan assets consisted of the following at December 31, 2021 and 2020: December 31, (in millions) 2021 2020 Projected benefit obligation $ 42.6 $ 74.5 Fair value of plan assets 39.9 65.7 Pension plans with accumulated benefit obligations in excess of plan assets consisted of the following at December 31, 2021 and 2020: December 31, (in millions) 2021 2020 Accumulated benefit obligation $ 40.0 $ 43.0 Fair value of plan assets 37.8 34.8 Net Periodic Benefit Cost (Income) Components of the net periodic benefit cost (income) were as follows: Years Ended December 31, (in millions) 2021 2020 2019 Service cost $ 0.3 $ 0.3 $ 0.3 Interest cost 0.9 1.2 1.5 Expected return on plan assets (2.8) (2.4) (2.4) Amortization of prior service cost — 0.1 0.1 Amortization of recognized actuarial loss 0.8 0.5 0.4 Other — — 0.1 Total net periodic benefit cost (income) $ (0.8) $ (0.3) $ — The components of net periodic benefit cost (income) other than service cost are presented in the Other (income) expense, net line on the Consolidated Statements of Earnings. The service cost component is presented within the Cost of goods sold, Research and development expenses, and Selling and administrative expenses lines on the Consolidated Statements of Earnings based on the nature of services performed by the related employees. Assumptions The Company determines actuarial assumptions on an annual basis. The actuarial assumptions used for the Company’s four defined benefit plans for non-U.S. participants will vary depending on the applicable country and as such, the tables below include these assumptions by country, as well as in total. The assumptions used in determining the benefit obligations were as follows: December 31, 2021 2020 Discount rate Philippines 5.25 % 4.00 % Taiwan 0.75 % 0.25 % United Kingdom 1.84 % 1.28 % Weighted-average 1.83 % 1.27 % Average wage increase Philippines 4.00 % 4.00 % Taiwan 4.00 % 4.00 % United Kingdom 4.65 % 4.20 % Weighted-average 4.59 % 4.18 % The assumptions used in determining the net periodic benefit cost (income) were as follows: Years Ended December 31, 2021 2020 2019 Discount rate Philippines 4.00 % 5.00 % 8.25 % Taiwan 0.25 % 0.75 % 1.25 % United Kingdom 1.28 % 2.00 % 2.80 % Weighted-average 1.27 % 1.97 % 2.78 % Average wage increase Philippines 4.00 % 5.00 % 6.00 % Taiwan 4.00 % 4.00 % 4.25 % United Kingdom 4.20 % 4.25 % 4.40 % Weighted-average 4.18 % 4.24 % 4.41 % Expected return on plan assets Taiwan 3.50 % 3.75 % 2.00 % United Kingdom 4.34 % 4.35 % 4.82 % Weighted-average 4.32 % 4.33 % 4.72 % The Company’s discount rate assumptions are determined by developing yield curves based on high quality corporate bonds with maturities matching the plans’ expected benefit payment streams. The plans’ expected cash flows are then discounted by the resulting year-by-year spot rates. Plan Assets The primary financial objective of the plans is to secure participant retirement benefits. Accordingly, the key objective in the plans’ financial management is to promote stability and, to the extent appropriate, growth in the funded status. Related and supporting financial objectives are established in conjunction with a review of current and projected plan financial requirements. As it relates to the funded defined benefit pension plans, the Company’s funding policy is consistent with the funding requirements of applicable local non-U.S. laws. The Company is responsible for overseeing the management of the investments of the plans’ assets and otherwise ensuring that the plans’ investment programs are in compliance with applicable local law, other relevant legislation, and related plan documents. Where relevant, the Company has retained professional investment managers to manage the plans’ assets and investment process. The investment managers, in executing their investment processes, have the authority and responsibility to select appropriate investments in the asset classes specified by the terms of their applicable prospectus or investment manager agreements with the plans. The assets of the plans are invested to achieve an appropriate return for the plans consistent with a prudent level of risk. The asset return objective is to achieve, as a minimum over time, the passively managed return earned by market index funds, weighted in the proportions outlined by the asset class exposures identified in the plans’ strategic allocation. The expected return on plan assets assumptions are developed through analysis of historical market returns, statistical analysis, current market conditions, and the past experience of plan asset investments. Fair Value Measurements The fair values of plan assets by asset category within the ASC 820 hierarchy were as follows at December 31, 2021 and 2020: December 31, 2021 December 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Asset category: Fixed income investments $ 3.5 $ 26.1 $ — $ 29.6 $ 3.4 $ 24.9 $ — $ 28.3 Common stock funds — 18.9 — 18.9 — 18.9 — 18.9 Real estate funds — 5.5 — 5.5 — 5.0 — 5.0 Cash and equivalents 0.5 — — 0.5 0.3 — — 0.3 Other 9.0 5.8 — 14.8 7.9 5.3 — 13.2 Total $ 13.0 $ 56.3 $ — $ 69.3 $ 11.6 $ 54.1 $ — $ 65.7 See Note 11. Hedging Transactions and Derivative Instruments for additional information on the fair value hierarchy. There were no significant transfers between Level 1 and Level 2 assets during the years ended December 31, 2021 and 2020. Fixed income investments include government and municipal securities and corporate bonds, which are valued based on yields currently available on comparable securities of issuers with similar credit ratings. Common stock funds consist of mutual funds and collective trusts. Mutual funds are valued by obtaining quoted prices from nationally recognized securities exchanges. Collective trusts are valued using Net Asset Value (the "NAV") as of the last business day of the year. The NAV is based on the underlying value of the assets owned by the fund minus its liabilities and then divided by the number of shares outstanding. The value of the underlying assets is based on quoted prices in active markets. The methods described above may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date. Future Estimates Benefit Payments Estimated future benefit payments to retirees, which reflect expected future service, are as follows: (in millions) 2022 $ 2.1 2023 1.9 2024 2.1 2025 2.6 2026 2.6 2027-2031 14.3 Contributions Generally, annual contributions are made at such times and in such amounts as required by law and agreed with the trustees of the non-U.S. defined benefit plans. The Company estimates it will pay $1.3 million during the year ended December 31, 2022 related to contributions to these plans. This amount may vary based on updated funding agreements with the trustees of these plans.

Other Comprehensive (Loss) Earn

Other Comprehensive (Loss) Earnings	12 Months Ended
	Dec. 31, 2021
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Other Comprehensive (Loss) Earnings	17. Other Comprehensive Earnings The amounts recognized in other comprehensive earnings (loss) were as follows: Year Ended December 31, 2021 (in millions) Pre-tax Tax Net of tax Foreign currency translation $ (3.6) $ — $ (3.6) Employee benefit plans 6.6 (1.6) 5.0 Changes in fair value of cash flow hedges (1.6) 0.3 (1.3) Total other comprehensive earnings $ 1.4 $ (1.3) $ 0.1 Year Ended December 31, 2020 (in millions) Pre-tax Tax Net of tax Foreign currency translation $ 13.8 $ — $ 13.8 Employee benefit plans (4.4) 1.0 (3.4) Changes in fair value of cash flow hedges 1.4 (0.3) 1.1 Total other comprehensive earnings $ 10.8 $ 0.7 $ 11.5 Year Ended December 31, 2019 (in millions) Pre-tax Tax Net of tax Foreign currency translation $ 1.3 $ — $ 1.3 Employee benefit plans (3.2) — (3.2) Changes in fair value of cash flow hedges 1.1 (0.2) 0.9 Total other comprehensive loss $ (0.8) $ (0.2) $ (1.0) The following table summarizes the changes in balances of each component of accumulated other comprehensive loss, net of tax during the years ended December 31, 2021 and 2020: (in millions) Cash flow hedges Employee benefit plans Cumulative foreign currency translation adjustments Total Balance at January 1, 2020 $ 0.5 $ (18.7) $ (93.8) $ (112.0) Other comprehensive earnings (loss), net of tax 1.1 (3.4) 13.8 11.5 Balance at December 31, 2020 1.6 (22.1) (80.0) (100.5) Other comprehensive (loss) earnings, net of tax (1.3) 5.0 (3.6) 0.1 Balance at December 31, 2021 $ 0.3 $ (17.1) $ (83.6) $ (100.4) The following table summarizes the amounts reclassified from accumulated other comprehensive loss to earnings: Years Ended December 31, (in millions) Statement of Earnings Line 2021 2020 2019 Pension and post-retirement benefit plans: Amortization or settlement of actuarial losses and prior service costs Other (income) expense, net $ 0.9 $ 0.7 $ 0.6 Tax (Benefit from) provision for income taxes (0.2) (0.1) (0.1) Net of tax $ 0.7 $ 0.6 $ 0.5 Cash flow hedges: Net (gains) losses reclassified into earnings Cost of goods sold $ (2.1) $ (1.2) $ 0.9 Tax (Benefit from) provision for income taxes 0.5 0.3 (0.2) Net of tax $ (1.6) $ (0.9) $ 0.7

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Segment Information	18. Segment Information The Company organizes its reportable segments based on how management analyzes performance, allocates capital, and makes strategic and operational decisions. These segments were determined in accordance with ASC 280, Segment Reporting. The segments are aligned around similar product applications serving our key end markets, to enhance focus on end market growth strategies. The Company’s operating segments engage in business activities from which they earn revenues and incur expenses, have discrete financial information available, and whose financial results are regularly reviewed and used by the chief operating decision maker to evaluate segment performance, allocate resources, and determine management incentive compensation. The Audio segment aggregates two operating segments into one reportable segment based on similar product applications serving our key end markets. The PD segment has one operating segment, which equals its reportable segment. The Company's two reportable segments are as follows: • Audio Segment Our Audio group designs and manufactures innovative audio products, including microphones, balanced armature speakers, and audio processors used in applications that serve the mobile, hearing health, True Wireless Stereo, Internet of Things, and computing markets. Audio has sales, support, and engineering facilities in North America, Europe, and Asia, as well as manufacturing facilities in Asia. • PD Segment Our PD group specializes in the design and delivery of high performance capacitor products and RF solutions for technically demanding applications. Our high performance capacitor products are used in applications such as power supplies and medical implants, which sell to a diverse set of customers for mission critical applications across the defense, medtech, industrial, electric vehicle, and communications markets. Our RF solutions solve a broad range of frequency filtering challenges for our customers, who use them in satellite communications and radar systems for defense applications. RF solutions are also used in mmWave 5G communications equipment. PD has sales, support, and engineering facilities in North America, Europe, and Asia as well as manufacturing facilities in North America and Asia. Information regarding the Company's reportable segments is as follows: Years Ended December 31, (in millions) 2021 2020 2019 Revenues: Audio $ 667.0 $ 591.2 $ 682.8 Precision Devices 201.1 173.1 172.0 Total revenues $ 868.1 $ 764.3 $ 854.8 Earnings from continuing operations before interest and income taxes: Audio $ 137.0 $ 44.9 $ 107.3 Precision Devices 43.7 31.7 30.4 Total segments 180.7 76.6 137.7 Corporate expense / other 61.9 48.9 56.9 Interest expense, net 14.2 16.4 14.5 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Depreciation and amortization: Audio $ 46.2 $ 47.0 $ 41.3 Precision Devices 13.3 10.5 9.9 Corporate 3.0 3.1 3.2 Total $ 62.5 $ 60.6 $ 54.4 Capital expenditures: Audio $ 40.8 $ 21.9 $ 24.0 Precision Devices 5.6 9.6 16.5 Corporate 2.2 0.4 0.7 Total $ 48.6 $ 31.9 $ 41.2 Research and development: Audio $ 81.8 $ 84.6 $ 90.8 Precision Devices 10.5 6.7 5.8 Corporate 0.5 1.6 0.2 Total $ 92.8 $ 92.9 $ 96.8 Information regarding assets of the Company's reportable segments: Total Assets December 31, (in millions) 2021 2020 Audio $ 1,467.1 $ 1,470.4 Precision Devices 260.4 179.2 Corporate / eliminations 4.1 5.3 Total $ 1,731.6 $ 1,654.9 The following table details revenues by geographic location. Revenues are attributed to regions based on the location of the Company's direct customer, which in some instances is an intermediary and not necessarily the end user. Long-lived assets are comprised of net property, plant, and equipment and operating lease right-of-use assets. These assets have been classified based on the geographic location of where they reside. The Company's businesses are based primarily in Asia, North America, and Europe. Revenues Long-Lived Assets Years Ended December 31, December 31, (in millions) 2021 2020 2019 2021 2020 Asia $ 611.5 $ 559.6 $ 614.7 $ 149.5 $ 140.5 United States 153.2 116.7 130.4 64.6 69.8 Europe 93.5 80.0 97.4 3.1 3.3 Other Americas 5.5 3.7 6.3 1.0 1.2 Other 4.4 4.3 6.0 — — Total $ 868.1 $ 764.3 $ 854.8 $ 218.2 $ 214.8 The Company's customers that accounted for 10% or more of total revenues were as follows: Revenues Years Ended December 31, 2021 2020 2019 Apple Inc. 16 % 23 % 22 %

Earnings per Share

Earnings per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Earnings per Share	19. Earnings per Share Basic and diluted earnings per share were computed as follows: Years Ended December 31, (in millions, except per share amounts) 2021 2020 2019 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Earnings (loss) from discontinued operations, net 0.2 3.7 (0.6) Net earnings $ 150.4 $ 6.6 $ 49.1 Basic earnings (loss) per common share: Earnings from continuing operations $ 1.63 $ 0.03 $ 0.55 Earnings (loss) from discontinued operations, net — 0.04 (0.01) Net earnings $ 1.63 $ 0.07 $ 0.54 Weighted-average shares outstanding 92.3 91.7 91.2 Diluted earnings (loss) per common share: Earnings from continuing operations $ 1.59 $ 0.03 $ 0.53 Earnings (loss) from discontinued operations, net — 0.04 — Net earnings $ 1.59 $ 0.07 $ 0.53 Diluted weighted-average shares outstanding 94.7 92.9 93.4

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2021
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Schedule II - Valuation and Qualifying Account	SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS Years Ended December 31, 2021, 2020, and 2019 Allowance for Doubtful Accounts (in millions) Balance at Charged to Cost and (1) Accounts Balance at Year Ended December 31, 2021 Allowance for Doubtful Accounts $ 1.6 (0.2) (1.2) $ 0.2 Year Ended December 31, 2020 Allowance for Doubtful Accounts $ 0.8 0.8 — $ 1.6 Year Ended December 31, 2019 Allowance for Doubtful Accounts $ 0.6 0.3 (0.1) $ 0.8 (1) Net of recoveries on previously reserved or written-off balances.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Accounting	Background - Knowles Corporation (NYSE:KN) is a market leader and global provider of advanced micro-acoustic microphones and balanced armature speakers, audio solutions, and high performance capacitors and radio frequency ("RF") products, serving the consumer electronics, medtech, defense, electric vehicle, industrial, and communications markets. The Company uses its leading position in SiSonic TM micro-electro-mechanical systems ("MEMS") microphones and strong capabilities in audio processing technologies to optimize audio systems and improve the user experience across consumer applications. Knowles is also a leader in hearing health acoustics, high performance capacitors, and RF solutions for a diverse set of markets. The Company's focus on the customer, combined with its 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. On May 3, 2021, the Company acquired all of the outstanding shares of common stock of Integrated Microwave Corporation ("IMC"), a manufacturer of RF filters. See Note 3. Acquisitions for additional information related to the transaction. On February 24, 2020, the Company announced that its Board of Directors had authorized a share repurchase program of up to $100 million of the Company's common stock. 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. The actual timing, number, and share price of shares repurchased will depend on a number of factors, including the market price of the Company’s common stock, general market and economic conditions, and applicable legal requirements. Any shares repurchased will be held as treasury stock. During the years ended December 31, 2021 and 2020, the Company repurchased 2,139,413 shares and 1,078,363 shares of common stock, respectively, for a total of $44.5 million and $16.2 million, respectively. On December 20, 2019, the Company acquired substantially all of the assets of the MEMS Microphone Application-specific integrated circuit Design Business (“ASIC Design Business”). See Note 3. Acquisitions for additional information related to the transaction. On January 3, 2019, the Company acquired substantially all of the assets of DITF Interconnect Technology, Inc. ("DITF"), a thin film components manufacturer. See Note 3. Acquisitions for additional information related to the transaction. Financial Statement Presentation - The Consolidated Financial Statements included in this Annual Report on Form 10-K are presented in conformity with U.S. generally accepted accounting principles ("U.S. GAAP").
Use of Estimates	Use of Estimates - The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying financial statements and disclosures. These estimates may be adjusted due to changes in future economic, industry, or customer financial conditions, as well as changes in technology or demand. Estimates are used in accounting for, among other items, inventory reserves, restructuring reserves, warranty reserves, pension and post-retirement plans, stock-based compensation, useful lives for depreciation and amortization of long-lived assets, future cash flows associated with impairment testing for goodwill, indefinite-lived intangible assets and other long-lived assets, deferred tax assets, uncertain income tax positions, changes in tax laws, and contingencies. Management uses historical experience and all available information to make these estimates, including considerations for the impact of the COVID-19 pandemic on the macroeconomic environment. The situation related to the COVID-19 pandemic continues to be complex and dynamic. The Company cannot reasonably estimate the duration of the COVID-19 pandemic or fully ascertain its impact on the Company’s future results and market capitalization, which could adversely impact estimates such as the recoverability of goodwill and long-lived assets and the realizability of deferred tax assets. Actual results may ultimately differ from estimates, although management does not believe such differences would materially affect the financial statements in any individual year. Estimates and assumptions are periodically reviewed and the effects of revisions are reflected in the Consolidated Financial Statements in the period that they are determined.
Cash and Cash Equivalents	Cash and Cash Equivalents - Cash and cash equivalents include cash on hand, demand deposits, and temporary cash investments with original maturities less than three months.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts – The Company maintains allowances for estimated losses as a result of customers' inability to make required payments. Management evaluates the aging of the accounts receivable balances, the financial condition of its customers, historical trends, relevant forecasts, and the time outstanding of specific balances to estimate the amount of accounts receivable that may not be collected in the future and records the appropriate provision.
Inventories	Inventories – Inventories are stated at the lower of cost or net realizable value, determined on the first-in, first-out ("FIFO") basis. The value of inventory may decline as a result of surplus inventory, price reductions, or technological obsolescence. It is the Company’s policy to carry reserves against the carrying value of inventory when items have no future demand (obsolete inventory) and additionally, where inventory items on hand have demand, yet have insufficient forecasted activity to consume the entire stock within a reasonable period. The Company recognizes reserves against the carrying value of such at-risk inventory items after considering the nature of the risk and any mitigating factors.
Property, Plant and Equipment	Property, Plant, and Equipment - Property, plant, and equipment includes the historic cost of land, buildings, equipment, and significant improvements to existing plant and equipment or, in the case of acquisitions, a fair market value appraisal of such assets completed at the time of acquisition. Property, plant, and equipment also includes the cost of purchased software. Expenditures for maintenance, repairs, and minor renewals are expensed as incurred. When property or equipment is sold or otherwise disposed of, the related cost and accumulated depreciation is removed from the respective accounts, and the gain or loss realized on disposition is reflected in earnings. The Company historically depreciates its assets on a straight-line basis over their estimated useful lives as follows: buildings and improvements 5 to 31.5 years; machinery and equipment 1.5 to 7 years; furniture and fixtures 2 to 5 years; vehicles 3 to 5 years; and software 3 to 5 years.
Lessee, Leases [Policy Text Block]	Leases - The Company determines whether an arrangement is a lease at contract inception. Lease liabilities and right-of-use assets are recognized on the lease commencement date based on the net present value of fixed lease payments over the lease term. The Company includes options to extend or terminate a lease within the lease term when it is reasonably certain the option will be exercised. Leases with an initial term of 12 months or less are not recorded on the Consolidated Balance Sheets. Lease liabilities represent an obligation to make lease payments arising from a lease while right-of-use assets represent a right to use an underlying asset during the lease term. Right-of-use assets include prepaid fixed lease payments and exclude lease incentives. As the Company's leases do not have a readily determinable implicit rate, the Company uses its incremental borrowing rate to determine the present value of fixed lease payments based on information available at the lease commencement date. Fixed lease expense for operating leases and right-of-use asset amortization for finance leases are generally recognized on a straight-line basis over the lease term. Variable lease payments, such as payments based on an index rate or usage, are expensed as incurred and excluded from lease liabilities and right-of-use assets. The Company combines lease components and nonlease components such as maintenance into a single lease component, which results in the capitalization of all fixed payments within lease liabilities and right-of-use assets.
Derivative Instruments	Derivative Instruments - The Company uses derivative financial instruments to hedge its exposure to foreign currency exchange rate risk. The Company does not enter into derivative financial instruments for speculative purposes and does not have a material portfolio of derivative financial instruments. Derivative financial instruments used for hedging purposes must be designated and effective as a hedge of the identified risk exposure at inception of the contract. The Company recognizes all derivatives as either assets or liabilities on the Consolidated Balance Sheets and measures those instruments at fair value. For derivatives designated as cash flow hedges, the effective portion of changes in the fair value of the derivatives is recorded as a component of other comprehensive earnings and subsequently recognized in net earnings when the hedged items impact earnings.
Goodwill and Intangible Assets	Goodwill and Indefinite-Lived Intangible Assets - Goodwill represents the excess of purchase consideration over the fair value of the net assets of businesses acquired. Goodwill and certain other intangible assets deemed to have indefinite lives are not amortized. Instead, goodwill and indefinite-lived intangible assets are tested for impairment at least annually, or more frequently if there are events or circumstances indicating the carrying value of individual reporting units or assets may exceed their respective fair values on a more likely than not basis. The Company performs its annual impairment assessment in the fourth quarter of each year on October 1. Recoverability of goodwill is measured at the reporting unit level. The Company has three reporting units. The goodwill balances associated with the Mobile Consumer Electronics ("MCE"), Hearing Health Technologies ("HHT"), and Precision Devices ("PD") reporting units were $741.0 million, $137.8 million, and $62.5 million, respectively, as of December 31, 2021. The impairment assessment compares the fair value of each reporting unit to its carrying value. Impairment is measured as the amount by which the carrying value of a reporting unit exceeds its fair value. Fair value is estimated using a discounted cash flow model that includes the Company’s market participant assumptions, forecasted future cash flows based on historical performance and future estimated results, determinations of appropriate discount rates, and other assumptions which are considered reasonable and inherent in the discounted cash flow analysis. Significant assumptions used in the assessment include forecasted revenue and terminal growth rates, profit margins, income taxes, and the Company's weighted average cost of capital. These assumptions require significant judgment and actual results may differ from estimated amounts. The fair value of all of the Company’s reporting units exceeded the carrying values by at least 35%, resulting in no goodwill impairment charges. Potential circumstances that could have a negative effect on the fair value of our reporting units include, but are not limited to, lower than forecasted growth rates or profit margins and changes in the weighted average cost of capital. A reduction in the estimated fair value of the reporting units could trigger an impairment in the future. The Company cannot predict the occurrence of certain events or changes in circumstances that might adversely affect the carrying value of goodwill and intangible assets. In testing its indefinite-lived trademarks for impairment, the Company uses a relief from royalty method to calculate and compare the fair value of the intangible asset to its carrying value. This method estimates the fair value of trademarks by calculating the present value of royalty income that could hypothetically be earned by licensing the trademark to a third party. Any excess of carrying value over the estimated fair value is recognized as an impairment loss. No impairment of indefinite-lived intangibles was indicated for the years ended December 31, 2021, 2020, or 2019. See Note 7. Goodwill and Other Intangible Assets for additional information on goodwill and indefinite-lived intangible assets. Other Intangible and Long-Lived Assets - Other intangible assets with determinable lives consist primarily of customer relationships, developed technology, and trademarks, which are amortized over estimated useful lives typically ranging from 5 to 10 years. There are no capitalized external legal costs incurred in the defense of patents as of December 31, 2021.
Foreign Currency	Foreign Currency - Assets and liabilities of non-U.S. subsidiaries, where the functional currency is not the U.S. dollar, are translated into U.S. dollars at year-end exchange rates. Revenue and expense items are translated using weighted-average yearly exchange rates. Foreign currency translation gains and losses are included as a component of Accumulated other comprehensive loss. Assets and liabilities of an entity that are denominated in currencies other than an entity’s functional currency are re-measured into the functional currency using end of period exchange rates or historical rates where applicable to certain balances. Gains and losses related to these re-measurements are recorded within the Consolidated Statements of Earnings as a component of Other (income) expense, net.
Revenue Recognition	Revenue Recognition - Revenue is recognized when control of the promised goods or services is transferred to the customer in an amount that reflects the consideration the Company expects to be entitled to in exchange for those goods or services. The majority of the Company’s revenue is generated through the manufacture and sale of a broad range of specialized products and components. For product and component sales, each good sold to a customer typically represents a distinct performance obligation. The Company’s performance obligation to provide goods to a customer is typically satisfied at a point in time upon completion of the shipping process as indicated by the terms of the contract, at which point control is transferred to the customer and revenue is recognized. The Company has no significant arrangements with multiple performance obligations. Remaining performance obligations consist of the aggregate amount of the total transaction price that is unsatisfied or partially satisfied. As of December 31, 2021 and 2020, our total remaining performance obligations were immaterial. The Company recognizes sales-based royalty revenue under third-party license agreements as the related sales are made by licensees. The terms of a contract or historical business practice can give rise to variable consideration, including customer discounts, rebates, and returns. The Company estimates variable consideration using either the expected value or most likely amount method. We include amounts in the transaction price to the extent it is probable that a significant reversal of revenue will not occur in a subsequent reporting period. Our estimates of variable consideration are based on all reasonably available information (historical, current, and forecasted). Rebates are recognized over the contract period based on expected revenue levels. Sales discounts and rebates totaled $5.0 million, $4.2 million, and $4.7 million for the years ended December 31, 2021, 2020, and 2019, respectively. Returns and allowances totaled $4.3 million, $5.4 million, and $6.6 million for the years ended December 31, 2021, 2020, and 2019, respectively. The Company accounts for shipping and handling activities that occur after control of the related good transfers to the customer as fulfillment activities rather than evaluating such activities as performance obligations. As a result, all shipping and handling costs related to contracts with customers are recognized in the Cost of goods sold line on the Consolidated Statements of Earnings. Additionally, the Company applies the practical expedient allowing incremental costs of obtaining a contract to be expensed as incurred if the amortization period of the resulting asset would have been less than one year. These costs primarily consist of sales commissions and the Company has no such significant costs exceeding the one year limit for applying the practical expedient. Receivables, net from contracts with customers were $137.7 million and $123.8 million as of December 31, 2021 and 2020, respectively. See Note 18. Segment Information for disclosures regarding the disaggregation of revenues.
Stock-Based Compensation	Stock-Based Compensation – The principal awards issued under the stock-based compensation plans include stock options, restricted stock units ("RSUs"), and performance share units ("PSUs"). The cost for such awards is measured at the grant date based on the fair value of the award. The value of the portion of the award that is expected to ultimately vest is generally recognized as expense on a straight-line basis, generally over the explicit service period and is included in Cost of goods sold, Research and development expenses, and Selling and administrative expenses in the Consolidated Statements of Earnings, depending on the functional area of the underlying employees. At the time of grant, the Company estimates forfeitures, based on historical experience, in order to estimate the portion of the award that will ultimately vest. The Company uses the Black-Scholes valuation model to estimate the fair value of stock options granted to employees. The fair value of each RSU granted is equal to the share price at the date of the grant. The fair value of each PSU is determined using a Monte Carlo simulation. The cost related to PSUs with performance conditions is recognized based on the expected attainment of performance targets. Changes in estimates for performance conditions that impact the number of shares expected to vest are recognized prospectively through cumulative adjustments. The cost for PSUs is recognized regardless of the expected attainment of market conditions as the grant date fair value considers the range of possible stock price and total shareholder return outcomes. See Note 14. Equity Incentive Program for additional information related to the Company’s stock-based compensation.
Income Taxes	Income Taxes - The Company records a provision for income taxes for the anticipated tax consequences of the reported results of operations using the asset and liability method. Under this method, the Company recognizes deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial reporting and tax bases of assets and liabilities, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using the tax rates that are expected to apply to taxable income for the years in which those tax assets and liabilities are expected to be realized or settled. The Company offsets and presents deferred tax liabilities and assets, as well as any related valuation allowance, as a single non-current amount on the Consolidated Balance Sheets on a jurisdictional basis. The Company's policy is to release income tax effects from accumulated other comprehensive loss in the period the underlying item expires. The Company establishes valuation allowances for its deferred tax assets if, based on all available positive and negative evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. In making such assessments, significant weight is given to evidence that can be objectively verified. The assessment of the need for a valuation allowance requires considerable judgment on the part of management with respect to the benefits that could be realized from future taxable income, as well as other positive and negative factors. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income, and tax-planning strategies in making this assessment. The Company recognizes tax benefits from uncertain tax positions only if it believes that it is more likely than not that the tax position will be sustained on examination by the taxing authorities based on the technical merits of the position. Adjustments are made to these reserves when facts and circumstances change, such as the closing of a tax audit or the refinement of an estimate. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will affect the provision for income taxes in the period in which such determination is made and could have a material impact on the Company's financial condition and operating results. The provision for income taxes includes the effects of any reserves that are believed to be appropriate, as well as the related net interest and penalties.
Research and development expense	Research and Development Costs – Research and development costs, including qualifying engineering costs, are expensed when incurred.
Deferred Charges, Policy	Other Assets and Deferred Charges - Investments in mutual funds of $6.4 million and $2.5 million are included in Other assets and deferred charges as of December 31, 2021 and 2020, respectively. These investments are carried at fair value based on quoted prices for identical assets in active markets, resulting in classification within Level 1 of the fair value hierarchy. Gains and losses related to the investments are recorded within the Consolidated Statements of Earnings as a component of Other (income) expense, net. Other assets and deferred charges also include non-current deferred tax assets.

Disposed and Discontinued Ope_2

Disposed and Discontinued Operations Discontinued Operations and Disposal Groups (Tables)	12 Months Ended
	Dec. 31, 2021
Discontinued Operations and Disposal Groups [Abstract]
Disposal Groups, Including Discontinued Operations	Management and the Board of Directors periodically conduct strategic reviews of the Company's businesses. On November 28, 2017, the Company completed the sale of its high-end oscillators business (“Timing Device Business”), part of the Precision Devices (“PD”) segment, for $130.0 million, plus purchase price adjustments for a net amount of $135.1 million. On July 7, 2016, the Company completed the sale of its speaker and receiver product line (“Speaker and Receiver Product Line”) for $45.0 million in cash, less purchase price adjustments for a net amount received of $40.6 million. In accordance with ASC 205-20, Presentation of Financial Statements – Discontinued Operations, the results of operations and financial positions of the Timing Device Business and Speaker and Receiver Product Line have been reclassified to discontinued operations for all periods presented as these disposals represent strategic shifts that had a major effect on the Company's results of operations. Summarized results of the Company's discontinued operations are as follows: Years Ended December 31, (in millions) 2021 2020 2019 Revenues $ — $ — $ — Operating income — — — Earnings from discontinued operations before taxes — — — (Benefit from) provision for income taxes (1) (0.2) (3.7) 0.6 Earnings (loss) from discontinued operations, net of tax $ 0.2 $ 3.7 $ (0.6) (1) The Company recorded a tax benefit for a refund received during the first quarter of 2020 related to the Timing Device Business. Assets and liabilities of discontinued operations are summarized below: (in millions) December 31, 2020 Liabilities of discontinued operations: Other liabilities (1) $ 0.6 Total liabilities $ 0.6 (1) This accrual was attributable to an unrecognized tax benefit recorded during the fourth quarter of 2019 related to the Speaker and Receiver Product Line. There were no assets and liabilities of discontinued operations as of December 31, 2021.

Property, Plant, and Equipment

Property, Plant, and Equipment (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Details of Impairment of Long-Lived Assets Held and Used by Asset	The Company evaluates long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The Company vacated its leased facility in Mountain View, California during the third quarter of 2020, resulting in its classification as a separate asset group. This facility was previously used by the Intelligent Audio product line, which is included within the Audio segment. Based on an assessment of market conditions, in particular the impact of the COVID-19 pandemic, the Company determined that the carrying amount of the asset group was not recoverable through undiscounted future cash flows, which included estimated sublease proceeds. The fair value of the operating lease right-of-use asset was determined by an estimate of discounted future cash flows that included estimated sublease proceeds and the determination of an appropriate discount rate based on market participant assumptions. The fair value measurements of operating lease right-of-use assets are based on significant unobservable inputs, and thus represent Level 3 inputs. Based on the excess of the carrying amount of the asset group over its fair value, the Company recorded an impairment loss of $5.4 million within Impairment charges in Operating expenses during the year ended December 31, 2020. During the third quarter of 2021, the Company determined that the remaining carrying amount of the asset group was not recoverable through undiscounted future cash flows, which included estimated sublease proceeds, due to the prolonged impact of the COVID-19 pandemic on market conditions. Based on the excess of the carrying amount of the asset group over its fair value, the Company recorded an impairment loss of $3.2 million within Impairment charges in Operating expenses during the year ended December 31, 2021. The Company entered into an operating lease for a research and development facility in Santa Clara, California during the first quarter of 2020 that did not commence until the second quarter of 2021. During the third quarter of 2020, the Company determined a loss was probable and reasonably estimable under ASC 450, Contingencies, based on its plan to sublet a significant portion of the facility due to the restructuring of the Intelligent Audio product line and the negative impact of the COVID-19 pandemic on market conditions. The estimated loss was determined by comparing the estimated carrying amount of the operating lease right-of-use asset to be recognized for the sublet portion of the facility upon lease commencement to an estimate of discounted future cash flows that included estimated sublease proceeds and the determination of an appropriate discount rate based on market participant assumptions. These measurements are based on significant unobservable inputs, and thus represent Level 3 inputs. The Company recorded an estimated loss of $2.2 million within Impairment charges in Operating expenses during the year ended December 31, 2020. The corresponding estimated liability, which was recorded in Other liabilities on the Consolidated Balance Sheets as of December 31, 2020, reduced the right-of-use asset upon lease commencement. The lease commenced during the second quarter of 2021, resulting in the recognition of operating lease liabilities of $4.0 million and right-of-use assets of $2.4 million. During the third quarter of 2021, the Company determined that the remaining carrying amount of the operating lease right-of-use asset was not recoverable through undiscounted future cash flows, which included estimated sublease proceeds, due to the prolonged impact of the COVID-19 pandemic on market conditions. Based on the excess of the carrying amount of the operating lease right-of-use asset over its fair value, the Company recorded an impairment loss of $0.8 million within Impairment charges in Operating expenses during the year ended December 31, 2021. No impairment charges were recorded during the year ended December 31, 2019. If actual results differ from estimated amounts, additional impairment charges may be recorded in the future.

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2021
Inventory, Net [Abstract]
Components of Inventory	(in millions) December 31, 2021 December 31, 2020 Raw materials $ 89.6 $ 89.7 Work in progress 33.6 31.0 Finished goods 66.7 48.4 Subtotal 189.9 169.1 Less reserves (36.8) (39.0) Total $ 153.1 $ 130.1

Property, Plant and Equipment_2

Property, Plant and Equipment, net (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Components of property, plant and equipment, net	(in millions) December 31, 2021 December 31, 2020 Land $ 12.9 $ 8.0 Buildings and improvements 119.3 111.9 Machinery, equipment, and other 575.0 562.8 Subtotal 707.2 682.7 Less accumulated depreciation (506.4) (491.2) Total $ 200.8 $ 191.5

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	The changes in the carrying value of goodwill by reportable segment for the years ended December 31, 2021 and 2020 are as follows: (in millions) Audio Precision Devices Total Balance at January 1, 2020 $ 878.7 $ 31.2 $ 909.9 Foreign currency translation 0.1 — 0.1 Balance at December 31, 2020 878.8 31.2 910.0 Acquisition — 31.3 31.3 Balance at December 31, 2021 $ 878.8 $ 62.5 $ 941.3
Schedule of Finite-Lived Intangible Assets	The gross carrying value and accumulated amortization for each major class of intangible assets are as follows: December 31, 2021 December 31, 2020 (in millions) Gross Carrying Accumulated Gross Carrying Accumulated Amortized intangible assets: Trademarks $ 2.0 $ 0.6 $ 1.0 $ 0.4 Patents — — 40.8 36.1 Customer relationships 36.4 5.9 12.0 5.2 Developed technology (1) 45.4 13.2 36.5 6.7 Other 2.4 1.2 1.8 0.7 Total 86.2 20.9 92.1 49.1 Unamortized intangible assets: Trademarks 32.0 32.0 IPR&D (1) — 3.7 Total 32.0 35.7 Total intangible assets, net $ 97.3 $ 78.7 (1) The in-process research and development ("IPR&D") project acquired with the ASIC Design Business was completed during the third quarter of 2021. The IPR&D asset has been reclassified as a definite-lived intangible asset to be amortized on a straight-line basis over an estimated useful life of 9 years.
Schedule of Intangible Assets	The gross carrying value and accumulated amortization for each major class of intangible assets are as follows: December 31, 2021 December 31, 2020 (in millions) Gross Carrying Accumulated Gross Carrying Accumulated Amortized intangible assets: Trademarks $ 2.0 $ 0.6 $ 1.0 $ 0.4 Patents — — 40.8 36.1 Customer relationships 36.4 5.9 12.0 5.2 Developed technology (1) 45.4 13.2 36.5 6.7 Other 2.4 1.2 1.8 0.7 Total 86.2 20.9 92.1 49.1 Unamortized intangible assets: Trademarks 32.0 32.0 IPR&D (1) — 3.7 Total 32.0 35.7 Total intangible assets, net $ 97.3 $ 78.7 (1) The in-process research and development ("IPR&D") project acquired with the ASIC Design Business was completed during the third quarter of 2021. The IPR&D asset has been reclassified as a definite-lived intangible asset to be amortized on a straight-line basis over an estimated useful life of 9 years.
Goodwill and Other Intangible Assets	7. Goodwill and Other Intangible Assets The changes in the carrying value of goodwill by reportable segment for the years ended December 31, 2021 and 2020 are as follows: (in millions) Audio Precision Devices Total Balance at January 1, 2020 $ 878.7 $ 31.2 $ 909.9 Foreign currency translation 0.1 — 0.1 Balance at December 31, 2020 878.8 31.2 910.0 Acquisition — 31.3 31.3 Balance at December 31, 2021 $ 878.8 $ 62.5 $ 941.3 The gross carrying value and accumulated amortization for each major class of intangible assets are as follows: December 31, 2021 December 31, 2020 (in millions) Gross Carrying Accumulated Gross Carrying Accumulated Amortized intangible assets: Trademarks $ 2.0 $ 0.6 $ 1.0 $ 0.4 Patents — — 40.8 36.1 Customer relationships 36.4 5.9 12.0 5.2 Developed technology (1) 45.4 13.2 36.5 6.7 Other 2.4 1.2 1.8 0.7 Total 86.2 20.9 92.1 49.1 Unamortized intangible assets: Trademarks 32.0 32.0 IPR&D (1) — 3.7 Total 32.0 35.7 Total intangible assets, net $ 97.3 $ 78.7 (1) The in-process research and development ("IPR&D") project acquired with the ASIC Design Business was completed during the third quarter of 2021. The IPR&D asset has been reclassified as a definite-lived intangible asset to be amortized on a straight-line basis over an estimated useful life of 9 years. As of December 31, 2021, the weighted average remaining useful lives for the amortizable intangible assets are: trademarks at 7.4 years, customer relationships at 7.0 years, developed technology at 5.3 years, and other at 5.1 years. Patents had no remaining useful life as of December 31, 2021. The weighted average remaining useful life in total for all amortizable intangible assets was 6.2 years as of December 31, 2021. Total amortization expense for the years ended December 31, 2021, 2020, and 2019 was $15.9 million, $13.0 million, and $7.0 million, respectively. Amortization expense for the next five years, based on current definite-lived intangible balances, is estimated to be as follows: (in millions) 2022 $ 12.2 2023 11.6 2024 11.6 2025 11.2 2026 5.3
Schedule of Future Amortization Expense	Amortization expense for the next five years, based on current definite-lived intangible balances, is estimated to be as follows: (in millions) 2022 $ 12.2 2023 11.6 2024 11.6 2025 11.2 2026 5.3

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Lease, Cost [Table Text Block]	The following table details the components of lease cost: Years Ended December 31, (in millions) 2021 2020 2019 Operating lease cost (1) $ 9.9 $ 9.9 $ 9.8 Finance lease cost: Amortization of right-of-use assets 2.3 2.1 2.2 Interest on lease liabilities 0.4 0.5 0.2 Sublease income (3.0) (3.0) (2.9) Total lease cost $ 9.6 $ 9.5 $ 9.3 (1) Includes short-term and variable lease costs, which were immaterial.
Schedule of Lease Assets and Liabilities [Table Text Block]	The following table presents supplemental balance sheet information related to finance leases: (in millions) Balance Sheet Line December 31, 2021 December 31, 2020 Finance lease right-of-use assets Property, plant, and equipment, net $ 8.1 $ 10.2 Current finance lease liabilities Other accrued expenses $ 2.7 $ 2.6 Long-term finance lease liabilities Other liabilities 3.6 5.5 Total finance lease liabilities $ 6.3 $ 8.1
Schedule of Lease Payments [Table Text Block]	The following table presents supplemental cash flow information related to leases: Years Ended December 31, (in millions) 2021 2020 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 10.2 $ 9.6 $ 10.4 Operating cash flows from finance leases 0.4 0.5 0.6 Financing cash flows from finance leases 2.3 2.0 1.7 Lease liabilities arising from obtaining right-of-use assets: Operating leases $ 6.5 $ 2.2 $ 2.6 Finance leases 0.3 0.1 0.3
Finance Lease, Liability, Maturity [Table Text Block]	The following table details weighted-average remaining lease terms and discount rates: December 31, 2021 December 31, 2020 Weighted-average remaining lease term (in years): Operating leases 3.1 3.7 Finance leases 3.1 4.1 Weighted-average discount rate: Operating leases 3.8 % 4.2 % Finance leases 5.4 % 5.5 %
Schedule of Maturities of Lease liabilities [Table Text Block]	The following table details maturities of lease liabilities as of December 31, 2021: (in millions) Operating Leases Finance Leases 2022 $ 12.1 $ 2.7 2023 8.5 2.7 2024 3.9 1.4 2025 2.0 — 2026 0.7 — 2027 and thereafter 0.2 — Total lease payments 27.4 6.8 Less interest (1.3) (0.5) Present value of lease liabilities $ 26.1 $ 6.3

Accrued Expenses and Other Li_2

Accrued Expenses and Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2021
Accrued Liabilities and Other Liabilities [Abstract]
Schedule of Accrued Expenses	The following table details the major components of other accrued expenses: (in millions) December 31, 2021 December 31, 2020 Sales volume rebates $ 4.9 $ 3.5 Accrued taxes other than income taxes 4.2 3.7 Current finance lease liabilities 2.7 2.6 Accrued insurance 1.7 1.7 Warranty 0.5 0.4 Restructuring and exit costs 0.4 2.4 Hedging liability 0.2 — Other 4.8 4.3 Total $ 19.4 $ 18.6
Schedule of Other Noncurrent Liabilities	The following table details the major components of other liabilities: (in millions) December 31, 2021 December 31, 2020 Deferred compensation, including defined benefit plans $ 13.9 $ 20.5 Long-term finance lease liabilities 3.6 5.5 Unrecognized tax benefits 2.0 1.5 Restructuring and exit costs — 0.2 Other (1) 1.1 5.1 Total $ 20.6 $ 32.8
Schedule of Product Warranty Liability	The changes in the carrying amount of product warranties were as follows: Years Ended December 31, (in millions) 2021 2020 2019 Beginning balance, January 1 $ 0.4 $ 0.9 $ 0.5 Provision for warranties 1.0 3.8 3.8 Settlements made (0.9) (4.3) (3.4) Ending balance, December 31 $ 0.5 $ 0.4 $ 0.9

Restructuring and Related Act_2

Restructuring and Related Activities (Tables)	12 Months Ended
	Dec. 31, 2021
Restructuring and Related Activities [Abstract]
Restructuring and Related Activities	10. Restructuring and Related Activities Restructuring and related activities are designed to better align the Company's operations with current market conditions through targeted facility consolidations, headcount reductions, and other measures to further optimize operations. No restructuring charges were recorded within Gross profit for the year ended December 31, 2021. During the year ended December 31, 2021, the Company recorded restructuring charges within Operating expenses of $0.5 million. These charges were primarily for actions associated with the Intelligent Audio product line, which is included within the Audio segment. During the year ended December 31, 2020, the Company restructured its Intelligent Audio product line. These actions resulted in a reduction in workforce and the refocusing of certain research and development activities. The Company recorded restructuring charges of $8.3 million related to these actions, including $5.4 million in severance pay and benefits, $1.7 million in fixed asset write-off costs, and $1.2 million in contract termination costs. In addition, during the year ended December 31, 2020, the Company recorded restructuring charges of $4.0 million for severance pay and benefits primarily to rationalize the remaining Audio segment workforce as a direct result of the lower demand the Company experienced due to the COVID-19 pandemic. During the year ended December 31, 2020, the Company recorded total restructuring charges within Gross profit of $2.3 million, primarily for fixed asset write-off costs and severance pay and benefits associated with the restructuring of the Intelligent Audio product line and other actions to rationalize the remaining Audio segment workforce. The Company also recorded total restructuring charges within Operating expenses of $10.0 million, primarily for severance pay and benefits and contract termination costs associated with the restructuring of the Intelligent Audio product line and other actions to rationalize the remaining Audio segment workforce. During the year ended December 31, 2019, the Company recorded restructuring charges of $1.7 million within Gross profit, primarily for actions associated with transferring certain operations of capacitors manufacturing to other existing facilities in order to further optimize operations in the PD segment, as well as rationalizing the Audio segment workforce. The Company also recorded restructuring charges of $4.3 million within Operating expenses, primarily for actions associated with rationalizing the Audio segment workforce. The following table details restructuring charges incurred by reportable segment for the periods presented: Years Ended December 31, (in millions) 2021 2020 2019 Audio $ 0.4 $ 10.5 $ 4.8 Precision Devices 0.1 0.1 0.8 Corporate — 1.7 0.4 Total $ 0.5 $ 12.3 $ 6.0 The following table details the Company’s severance and other restructuring accrual activity: (in millions) Severance Pay and Benefits Contract Termination and Other Costs Total Balance at January 1, 2019 $ 0.8 $ — $ 0.8 Restructuring charges 6.0 — 6.0 Payments (5.4) — (5.4) Balance at December 31, 2019 1.4 — 1.4 Restructuring charges 9.4 1.2 10.6 Payments (8.9) (0.5) (9.4) Balance at December 31, 2020 1.9 0.7 2.6 Restructuring charges 0.5 — 0.5 Payments (2.0) (0.7) (2.7) Balance at December 31, 2021 $ 0.4 $ — $ 0.4 The severance and restructuring accruals are recorded in the following line items on the Consolidated Balance Sheets: (in millions) December 31, 2021 December 31, 2020 Other accrued expenses $ 0.4 $ 2.4 Other liabilities — 0.2 Total $ 0.4 $ 2.6
Schedule of Restructuring and Related Costs	The following table details restructuring charges incurred by reportable segment for the periods presented: Years Ended December 31, (in millions) 2021 2020 2019 Audio $ 0.4 $ 10.5 $ 4.8 Precision Devices 0.1 0.1 0.8 Corporate — 1.7 0.4 Total $ 0.5 $ 12.3 $ 6.0
Schedule of Restructuring Reserve by Type of Cost	The following table details the Company’s severance and other restructuring accrual activity: (in millions) Severance Pay and Benefits Contract Termination and Other Costs Total Balance at January 1, 2019 $ 0.8 $ — $ 0.8 Restructuring charges 6.0 — 6.0 Payments (5.4) — (5.4) Balance at December 31, 2019 1.4 — 1.4 Restructuring charges 9.4 1.2 10.6 Payments (8.9) (0.5) (9.4) Balance at December 31, 2020 1.9 0.7 2.6 Restructuring charges 0.5 — 0.5 Payments (2.0) (0.7) (2.7) Balance at December 31, 2021 $ 0.4 $ — $ 0.4
Schedule of Restructuring Reserve by Balance Sheet Location	The severance and restructuring accruals are recorded in the following line items on the Consolidated Balance Sheets: (in millions) December 31, 2021 December 31, 2020 Other accrued expenses $ 0.4 $ 2.4 Other liabilities — 0.2 Total $ 0.4 $ 2.6

Hedging Transactions and Deriva

Hedging Transactions and Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivative Instruments	The fair values of derivative instruments held by the Company are as follows (in millions): Derivative Assets (Liabilities) Hedge Type Contract Type Balance Sheet Line December 31, 2021 December 31, 2020 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Prepaid and other current assets $ 0.7 $ 2.1 Cash flow hedges Foreign exchange contracts Other accrued expenses (0.2) — Derivatives not designated as hedging instruments Economic hedges Foreign exchange contracts Prepaid and other current assets 0.3 0.4
Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance	11. Hedging Transactions and Derivative Instruments The Company is affected by changes in certain market conditions. These changes in market conditions may adversely impact the Company’s financial performance and are referred to as "market risks." The Company uses derivatives as a risk management tool to mitigate the potential impact of certain market risks, which are primarily foreign currency risk related to ongoing business operations. Cash Flow Hedging The Company uses cash flow hedges to minimize the variability in cash flows of assets, liabilities, or forecasted transactions caused by fluctuations in foreign currency exchange rates. These derivatives, which are designated cash flow hedges, are carried at fair value. The changes in their fair values are recorded to Accumulated Other Comprehensive Income (Loss) ("AOCI") and reclassified in current earnings when the hedge contract matures or becomes ineffective. To manage its exposure to foreign currency exchange rates, the Company has entered into currency deliverable forward contracts. These derivative instruments allow the Company to hedge portions of its forecasted intercompany sales, which are expected to occur within the next twelve months and are denominated in non-functional currencies. The Company maintains a foreign currency cash flow hedging program primarily to reduce the risk that the net U.S. dollar cash inflows from non-U.S. dollar sales and non-U.S. dollar net cash outflows from procurement activities will be adversely affected by changes in foreign currency exchange rates. At December 31, 2021 and 2020, the notional value of the derivatives related to currency forward contracts, principally the Chinese yuan, Malaysian ringgit, and Philippine peso, was $59.4 million and $69.0 million, respectively. The Company presents the impact of foreign exchange contracts qualifying as cash flow hedges within the Cost of goods sold line on the Consolidated Statements of Earnings, which is the same line used to present the earnings effect of the hedged item. Economic (Non-Designated) Hedging In addition to derivative instruments that are designated and qualify for hedge accounting, the Company also uses certain derivatives as economic hedges of foreign currency risk. Although these derivatives were not designated and/or did not qualify for hedge accounting, they are effectively economic hedges. The changes in fair value of these economic hedges are immediately recognized in earnings. The Company uses foreign currency economic hedges to offset the earnings impact that fluctuations in foreign currency exchange rates have on certain monetary assets and liabilities denominated in non-functional currencies. The Company does not enter into these hedges for speculative reasons. These derivatives are carried at fair value with changes in fair value immediately recognized in earnings within Other (income) expense, net. In addition, these derivative instruments minimize the impact of exchange rate movements on the Company’s balance sheet, as the gains or losses on these derivatives are intended to offset gains and losses from the reduction of the hedged assets and liabilities. At December 31, 2021 and 2020, the notional value of the derivatives related to economic hedging was $93.2 million and $77.1 million, respectively. The notional amounts of the derivative financial instruments do not necessarily represent amounts exchanged by the parties and, therefore, are not a direct measure of our exposure to the financial risks described above. The amounts exchanged are calculated by reference to the notional amounts and by other terms of the derivatives, such as foreign currency exchange rates or other financial indices. The Company does not view the fair values of its derivatives in isolation, but rather in relation to the fair values or cash flows of the underlying hedged transactions or other exposures. Virtually all of our derivatives are straightforward over-the-counter instruments with liquid markets. Fair Value Measurements All derivatives are carried at fair value on the Company’s Consolidated Balance Sheets. ASC 820, Fair Value Measurement, establishes a fair value hierarchy that requires the Company to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. A financial instrument’s categorization within the hierarchy is based on the lowest level of input that is significant to the fair value measurement. ASC 820 establishes three levels of inputs that may be used to measure fair value as follows: Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 - Observable inputs other than quoted prices included in Level 1, such as quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of assets or liabilities. Level 3 - Unobservable inputs for which little or no market data exists, therefore requiring an entity to develop its own assumptions. The Company determines the fair values of its derivatives based on standard valuation models or observable market inputs such as quoted market prices or foreign currency exchange rates; therefore, the Company classifies the derivatives within Level 2 of the valuation hierarchy. The fair values of derivative instruments held by the Company are as follows (in millions): Derivative Assets (Liabilities) Hedge Type Contract Type Balance Sheet Line December 31, 2021 December 31, 2020 Derivatives designated as hedging instruments Cash flow hedges Foreign exchange contracts Prepaid and other current assets $ 0.7 $ 2.1 Cash flow hedges Foreign exchange contracts Other accrued expenses (0.2) — Derivatives not designated as hedging instruments Economic hedges Foreign exchange contracts Prepaid and other current assets 0.3 0.4 The pre-tax amount of unrealized gain recognized in accumulated other comprehensive loss on derivatives designated as hedging instruments is as follows (in millions): Years Ended December 31, Hedge Type Contract Type 2021 2020 2019 Cash flow hedges Foreign exchange contracts $ 0.5 $ 2.6 $ 0.2 The table above excludes tax expense of $0.2 million and $0.6 million for the years ended December 31, 2021 and 2020, respectively. There was no tax benefit or expense for the year ended December 31, 2019. The pre-tax impact of derivatives on the Consolidated Statements of Earnings is as follows (in millions): Years Ended December 31, 2021 2020 2019 Hedge Type Contract Type Cost of goods sold Other (income) expense, net Cost of goods sold Other (income) expense, net Cost of goods sold Other (income) expense, net Total amounts per Consolidated Statements of Earnings $ 508.6 $ (3.0) $ 490.8 $ 1.5 $ 525.1 $ 0.4 Effect of derivatives designated as hedging instruments Amount of (gain) loss reclassified from accumulated other comprehensive loss into earnings: Cash flow hedges Foreign exchange contracts (2.1) — (1.2) — 0.9 — Effect of derivatives not designated as hedging instruments Amount of gain recognized in earnings: Economic hedges Foreign exchange contracts — (1.4) — (2.9) — (0.9)

Borrowings and Lines of Credit

Borrowings and Lines of Credit (Tables)	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Borrowings (net of debt issuance costs, debt discount, and amortization) consist of the following: (in millions) December 31, 2021 December 31, 2020 3.25% convertible senior notes $ — $ 165.1 Revolving credit facility 70.0 — Total 70.0 165.1 Less current maturities — 165.1 Total long-term debt $ 70.0 $ — Total debt principal payments over the next five years are as follows: (in millions) 2022 2023 2024 2025 2026 Debt principal payments $ — $ — $ 70.0 $ — $ —
Convertible Debt	3.25% Convertible Senior Notes Due November 1, 2021 In May 2016, the Company issued $172.5 million aggregate principal amount of 3.25% convertible senior notes which were due November 1, 2021 (the "Notes"). Interest was payable semiannually in arrears on May 1 and November 1 of each year. The Notes were governed by an Indenture between the Company, as issuer, and U.S. Bank National Association as trustee. Upon conversion, the Company could elect to pay or deliver cash, shares of the Company's common stock, or a combination of cash and shares of common stock. The conversion rate was 54.2741 shares of common stock per $1,000 principal amount of Notes. The conversion price was $18.4250 per share of common stock. The Notes were senior unsecured obligations. The Notes matured on November 1, 2021. The Company settled the principal amount of $172.5 million in cash and the excess conversion value by delivering 0.4 million shares of its common stock held in treasury. The shares of common stock delivered to settle the excess conversion value of the Notes were offset by shares received under the convertible note hedge transactions described below. Settlement of the excess conversion value resulted in a $5.9 million decrease in treasury stock, which was measured based on the acquisition cost of the delivered shares determined on a FIFO basis, offset by an equivalent decrease in additional paid-in capital with no net impact to equity. In accounting for the issuance of the Notes, the Company separated the Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of a similar liability that did not have an associated convertible feature. The carrying amount of the equity component representing the conversion option was determined by deducting the fair value of the liability component from the face value of the Notes as a whole. The excess of the principal amount of the liability component over its carrying amount was amortized to interest expense over the term of the Notes. The equity component recorded within additional paid-in capital of $29.9 million was not remeasured as it continued to meet the conditions for equity classification. The Notes consisted of the following: (in millions) December 31, 2020 Liability component: Principal $ 172.5 Less debt issuance costs and debt discount, net of amortization (7.4) Total 165.1 Less current maturities 165.1 Long-term portion $ — The total estimated fair value of the Notes at December 31, 2020 was $196.5 million. The fair value was determined based on the closing trading price of the Notes as of the last trading day of 2020. The following table sets forth total interest expense recognized related to the Notes: Years Ended December 31, (in millions) 2021 2020 2019 3.25% coupon $ 4.7 $ 5.6 $ 5.6 Amortization of debt issuance costs 0.8 0.9 0.9 Amortization of debt discount 6.6 7.4 6.8 Total $ 12.1 $ 13.9 $ 13.3 Note Hedges To minimize the impact of potential economic dilution upon conversion of the Notes, the Company entered into convertible note hedge transactions (the “Note Hedges”) with respect to its common stock. In the second quarter of 2016, the Company paid an aggregate amount of $44.5 million for the Note Hedges. The Note Hedges were separate transactions entered into by the Company, and are not part of the Notes or the Warrants, and were accounted for as part of additional paid-in capital. Holders of the Notes did not have any rights with respect to the Note Hedges. The Company exercised its rights under the Note Hedges upon maturity of the Notes, which resulted in the receipt of 0.4 million shares of its common stock to be held in treasury. These transactions resulted in a $7.6 million increase in treasury stock, which was measured based on the prevailing fair market value of the shares received, offset by an equivalent increase in additional paid-in capital with no net impact to equity. Warrants In addition to the Note Hedges, in the second quarter of 2016, the Company entered into warrant transactions, whereby the Company sold warrants to acquire shares of the Company's common stock at a strike price of $21.1050 per share (the “Warrants”). The Company received aggregate proceeds of $39.1 million from the sale of the Warrants. The Warrants expire during the first quarter of 2022. If the market price per share of the Company's common stock for the reporting period, as measured under the Warrants, exceeds the strike price of the Warrants, the Warrants would have a dilutive effect on the Company's common stock. The Warrants are separate transactions entered into by the Company, and are not part of the Notes or the Note Hedges, and have been accounted for as part of additional paid-in capital. Holders of the Notes and Note Hedges do not have any rights with respect to the Warrants.
Schedule of Term Loan and Revolving Credit Facilities	Revolving Credit Facility Revolving credit facility borrowings consist of the following: (in millions) December 31, 2021 December 31, 2020 $400.0 million revolving credit facility $ 70.0 $ — Less current maturities — — Long-term portion $ 70.0 $ — On September 4, 2020, the Company entered into a new Credit Agreement (the "New Credit Agreement"). The New Credit Agreement provides for a senior secured revolving credit facility (the "New Credit Facility") with borrowings in an aggregate principal amount at any time outstanding not to exceed $400.0 million. Up to $100.0 million of the New Credit Facility will be available in Euro, Pounds Sterling, and other currencies requested by the Company and agreed to by each Lender and up to $50.0 million of the New Credit Facility will be made available in the form of letters of credit denominated in currencies approved by the issuing banks. The New Credit Agreement serves as refinancing of indebtedness and terminates the Company's Revolving Credit Facility Agreement dated as of October 11, 2017 ("Prior Credit Facility"). The Prior Credit Facility consisted of a $400.0 million senior secured revolving credit facility. At any time during the term of the New Credit Facility, the Company will be permitted to increase the commitments under the New Credit Facility or to establish one or more incremental term loan facilities under the New Credit Facility in an aggregate principal amount not to exceed $200.0 million for all such incremental facilities. Commitments under the New Credit Facility will terminate, and loans outstanding thereunder will mature, on January 2, 2024. The New Credit Agreement includes requirements, to be tested quarterly, that the Company maintains (i) a minimum ratio of Consolidated EBITDA to consolidated interest expense of 3.25 to 1.0, (the "Interest Coverage Ratio"), (ii) a maximum ratio of Consolidated total indebtedness to Consolidated EBITDA of 3.75 to 1.0 (the "Total Leverage Ratio"), and (iii) a maximum ratio of senior secured indebtedness to Consolidated EBITDA of 3.25 to 1.0 (the "Senior Secured Leverage Ratio"). For these ratios, Consolidated EBITDA and consolidated interest expense are calculated using the most recent four consecutive fiscal quarters in a manner defined in the New Credit Agreement. At December 31, 2021, the Company was in compliance with these covenants and it expects to remain in compliance with all of its debt covenants over the next twelve months. The interest rates under the New Credit Facility will be, at the Borrowers' option (1) LIBOR (or EURIBOR for borrowings denominated in Euro; or SONIA for borrowings denominated in Pounds Sterling) plus the rates per annum determined from time to time based on the total leverage ratio of the Company as of the end of and for the most recent period of four fiscal quarters for which financial statements have been delivered (the "Applicable Margin"); or (2) in the case of borrowings denominated in U.S. dollars, alternate base rate ("ABR") (as defined in the New Credit Agreement) plus the Applicable Margin. The Applicable Margin for LIBOR could range from 1.50% to 2.50% while the Applicable Margin for ABR could range from 0.50% to 1.50%. Prior to the discontinuation of the relevant LIBOR reference rate on June 30, 2023, the Company and its lenders will agree on an ABR to address the replacement of LIBOR for the remaining life of the New Credit Facility. The interest rate under the New Credit Facility is variable based on LIBOR at the time of the borrowing and the Applicable Margin. In addition, a commitment fee accrues on the average daily unused portion of the New Credit Facility at a rate of 0.225% to 0.375%.
Schedule of Interest Expense and Interest Income	Interest expense and interest income for the years ended December 31, 2021, 2020, and 2019 were as follows: Years Ended December 31, (in millions) 2021 2020 2019 Interest expense $ 14.4 $ 17.1 $ 15.3 Interest income (0.2) (0.7) (0.8) Interest expense, net $ 14.2 $ 16.4 $ 14.5

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	The components of earnings before income taxes and discontinued operations were: Years Ended December 31, (in millions) 2021 2020 2019 Domestic $ 15.5 $ (26.2) $ (48.3) Foreign 89.1 37.5 114.6 Total earnings before income taxes and discontinued operations $ 104.6 $ 11.3 $ 66.3
Schedule of Components of Income Tax Expense (Benefit)	Income tax (benefit) expense for the years ended December 31, 2021, 2020, and 2019 is comprised of the following: Years Ended December 31, (in millions) 2021 2020 2019 Current: U.S. Federal $ 0.4 $ 0.7 $ 0.7 State and local 0.3 0.2 0.2 Foreign 14.8 10.3 15.9 Total current tax expense $ 15.5 $ 11.2 $ 16.8 Deferred: U.S. Federal $ (57.1) $ (0.4) $ 0.1 State and local (2.6) 0.2 (0.1) Foreign (1.4) (2.6) (0.2) Total deferred tax benefit (61.1) (2.8) (0.2) Total income tax (benefit) expense $ (45.6) $ 8.4 $ 16.6
Schedule of Effective Income Tax Rate Reconciliation	The reconciliation of the U.S. Federal income tax rate to the Company’s effective income tax rate was as follows: Years Ended December 31, 2021 2020 2019 U.S. Federal income tax rate 21.0 % 21.0 % 21.0 % State and local taxes, net of Federal income tax benefit 0.3 % 4.2 % 0.2 % Foreign operations tax effect 3.3 % 17.3 % 5.0 % Research and experimentation tax credits (3.8) % (29.5) % (5.0) % Valuation allowance (57.1) % 85.4 % 15.0 % Tax contingencies 0.6 % 0.3 % 1.3 % Tax holiday (10.1) % (37.8) % (24.6) % Foreign taxes 1.0 % 2.8 % 2.1 % Non-deductible and non-taxable interest (0.2) % 1.0 % (2.9) % Stock-based compensation 4.8 % 11.3 % 3.0 % Other, principally non-tax deductible items 0.1 % 1.1 % 0.3 % Global low tax and foreign derived intangible income (2.3) % 12.1 % 10.6 % Foreign currency adjustments (0.7) % (6.1) % — % Prior period items (0.5) % (8.8) % (1.0) % Effective income tax rate (43.6) % 74.3 % 25.0 %
Schedule of Deferred Tax Assets and Liabilities	The components of the Company’s deferred tax assets and liabilities included the following: (in millions) December 31, 2021 December 31, 2020 Deferred tax assets: Accrued compensation, principally post-retirement, and other employee benefits $ 10.4 $ 14.1 Accrued expenses, principally for state income taxes and warranty 6.1 8.6 Accrued interest 5.9 7.7 Net operating loss and other carryforwards 70.9 71.6 Inventories, principally due to reserves for financial reporting purposes and capitalization for tax purposes 7.7 6.5 Convertible note hedges — 1.8 Unremitted earnings of non-U.S. subsidiaries 1.6 — Intangible assets, principally due to different tax and financial reporting bases 0.6 — Plant and equipment, principally due to differences in depreciation 17.0 13.0 Total gross deferred tax assets 120.2 123.3 Valuation allowance (39.1) (98.0) Total deferred tax assets $ 81.1 $ 25.3 Deferred tax liabilities: Intangible assets, principally due to different tax and financial reporting bases $ — $ (4.3) Debt discount on convertible notes — (1.4) Unremitted earnings of non-U.S. subsidiaries — (0.9) Other liabilities (3.0) (0.8) Total gross deferred tax liabilities (3.0) (7.4) Net deferred tax asset $ 78.1 $ 17.9 Classified as follows in the Consolidated Balance Sheets: Other assets and deferred charges (non-current deferred tax assets) $ 78.7 $ 19.9 Deferred income taxes (non-current deferred tax liabilities) (0.6) (2.0) Net deferred tax asset $ 78.1 $ 17.9
Schedule of Unrecognized Tax Benefits Roll Forward	Unrecognized Tax Benefits The Company records interest and penalties associated with unrecognized tax benefits as a component of income tax expense. During the years ended December 31, 2021, 2020, and 2019, the Company recorded no potential interest benefit or expense. There was no accrued interest at December 31, 2021, 2020 and 2019. There was no recorded potential penalty expense during the years ended December 31, 2021, 2020, and 2019. Total accrued penalties at December 31, 2021, 2020, and 2019 of $0.3 million were included in Other liabilities on the Consolidated Balance Sheets. The Company's tax returns are routinely audited by the tax authorities in the relevant jurisdictions. For tax years before 2017, the Company is no longer subject to U.S. federal income tax examination. For tax years before 2015, the Company’s Malaysian principal subsidiary is no longer subject to examination. Included in the balance of total unrecognized tax benefits at December 31, 2021 are potential benefits of $2.0 million, which if recognized, would affect the effective rate on earnings from continuing operations. Given the Company's current valuation allowance position, no benefit is expected to result from the reversal of any uncertain tax position associated with the acquired attributes. Unrecognized tax benefits at January 1, 2019 $ 10.1 Additions for tax positions of prior years 2.8 Reductions for tax positions of prior years (0.1) Settlements (0.1) Unrecognized tax benefits at December 31, 2019 $ 12.7 Settlements (2.6) Foreign exchange fluctuations 0.1 Unrecognized tax benefits at December 31, 2020 $ 10.2 Reductions for tax positions of prior years (0.3) Settlements (0.4) Unrecognized tax benefits at December 31, 2021 $ 9.5

Equity Incentive Program (Table

Equity Incentive Program (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Share-Based Compensation Recognized Period Costs	The following table summarizes the stock-based compensation expense recognized by the Company for the periods presented: Years Ended December 31, (in millions) 2021 2020 2019 Pre-tax stock-based compensation expense Cost of goods sold $ 1.6 $ 1.7 $ 1.5 Research and development expenses 5.5 6.2 7.7 Selling and administrative expenses 25.0 9.4 16.0 Total pre-tax stock-based compensation expense 32.1 17.3 25.2 Tax benefit 5.1 — — Total stock-based compensation expense, net of tax $ 27.0 $ 17.3 $ 25.2
Schedule of Black-Scholes Option-Pricing Assumptions	The fair value of stock options granted by the Company was estimated on the date of grant using a Black-Scholes option-pricing model based on the assumptions shown in the table below. Years Ended December 31, 2021 2020 2019 Risk-free interest rate 0.06% 0.11% to 1.42% 1.55% to 2.44% Dividend yield —% —% —% Expected life (years) 4.5 4.3 to 4.5 4.5 Volatility 36.0% 38.8% to 40.6% 40.0% to 42.9% Fair value at date of grant $6.14 to $6.31 $4.78 to $5.95 $6.22 to $7.45
Schedule of SSAR and Stock Options Activity	The following table summarizes the Company's stock-settled stock appreciation right ("SSAR") and stock option activity for the year ended December 31, 2021. SSARs Stock Options Number of Shares Weighted-Average Exercise Price Aggregate Intrinsic Value Weighted-Average Remaining Contractual Term (Years) Number of Shares Weighted-Average Exercise Price Aggregate Intrinsic Value Weighted-Average Remaining Contractual Term (Years) (in millions, except share and per share amounts) Outstanding at December 31, 2020 596,537 $ 22.72 5,765,903 $ 17.44 Granted — — 220,963 20.61 Exercised (114,096) 21.77 (1,540,314) 16.64 Forfeited — — (119,662) 17.35 Expired (106,477) 22.17 (848,452) 29.52 Outstanding at December 31, 2021 375,964 $ 23.16 $ 0.2 0.8 3,478,438 $ 15.04 $ 28.9 3.1 Exercisable at December 31, 2021 375,964 $ 23.16 $ 0.2 0.8 2,645,456 $ 14.25 $ 24.1 2.4
Schedule of Other Share-based Compensation, Activity	Other information regarding the exercise of SSARs and stock options is listed below: Years Ended December 31, (in millions) 2021 2020 2019 SSARs Aggregate intrinsic value of SSARs exercised $ 0.1 $ — $ 0.4 Stock Options Cash received by Knowles for exercise of stock options $ 25.6 $ 1.8 $ 9.8 Aggregate intrinsic value of stock options exercised 6.6 0.4 2.7 Tax benefit from stock options exercised 1.2 — —
Schedule of Restricted Stock Units Award Activity	The following table summarizes the Company's RSU activity for the year ended December 31, 2021: Share units Weighted-average grant date fair value Unvested at December 31, 2020 1,909,786 $ 16.14 Granted 1,159,374 20.59 Vested (1) (1,068,104) 15.81 Forfeited (222,417) 18.42 Unvested at December 31, 2021 1,778,639 $ 18.89
Share-based Payment Arrangement, Performance Shares, Outstanding Activity [Table Text Block]	14. Equity Incentive Program The Company maintains equity compensation plans that provide for the issuance of Knowles stock to directors, executive officers, and other employees. The maximum number of shares available for issuance under the plans is 16.1 million, of which 11.0 million were available for future awards at December 31, 2021. The following table summarizes the stock-based compensation expense recognized by the Company for the periods presented: Years Ended December 31, (in millions) 2021 2020 2019 Pre-tax stock-based compensation expense Cost of goods sold $ 1.6 $ 1.7 $ 1.5 Research and development expenses 5.5 6.2 7.7 Selling and administrative expenses 25.0 9.4 16.0 Total pre-tax stock-based compensation expense 32.1 17.3 25.2 Tax benefit 5.1 — — Total stock-based compensation expense, net of tax $ 27.0 $ 17.3 $ 25.2 Compensation expense for stock-based awards is measured based on the fair value of the awards as of the date the stock-based awards are granted and adjusted to the estimated number of awards that are expected to vest. Forfeitures are estimated based on historical experience at the time of grant and revised in subsequent periods if actual forfeitures differ from those estimates. Compensation costs for stock-based awards are amortized over their service period. Stock Option s and SSARs The fair value of stock options granted by the Company was estimated on the date of grant using a Black-Scholes option-pricing model based on the assumptions shown in the table below. Years Ended December 31, 2021 2020 2019 Risk-free interest rate 0.06% 0.11% to 1.42% 1.55% to 2.44% Dividend yield —% —% —% Expected life (years) 4.5 4.3 to 4.5 4.5 Volatility 36.0% 38.8% to 40.6% 40.0% to 42.9% Fair value at date of grant $6.14 to $6.31 $4.78 to $5.95 $6.22 to $7.45 Expected volatilities are based on the historical volatility of the Company’s stock. The risk-free interest rate is based on U.S. government issues with a remaining term equal to the expected life of the stock options. The expected term is the period over which our employees are expected to hold their options. It is based on the simplified method from the SEC’s safe harbor guidelines. The Company does not currently anticipate paying dividends over the expected term. The exercise price per share for the stock options granted by the Company was equal to the closing price of Knowles' stock on the NYSE on the date of the grant. The period during which options granted by the Company were exercisable was fixed by Knowles' Compensation Committee of the Board of Directors at the time of grant. Generally, stock options vest one-third on each of the first three anniversaries of the grant date and expire 7 years from the grant date. The following table summarizes the Company's stock-settled stock appreciation right ("SSAR") and stock option activity for the year ended December 31, 2021. SSARs Stock Options Number of Shares Weighted-Average Exercise Price Aggregate Intrinsic Value Weighted-Average Remaining Contractual Term (Years) Number of Shares Weighted-Average Exercise Price Aggregate Intrinsic Value Weighted-Average Remaining Contractual Term (Years) (in millions, except share and per share amounts) Outstanding at December 31, 2020 596,537 $ 22.72 5,765,903 $ 17.44 Granted — — 220,963 20.61 Exercised (114,096) 21.77 (1,540,314) 16.64 Forfeited — — (119,662) 17.35 Expired (106,477) 22.17 (848,452) 29.52 Outstanding at December 31, 2021 375,964 $ 23.16 $ 0.2 0.8 3,478,438 $ 15.04 $ 28.9 3.1 Exercisable at December 31, 2021 375,964 $ 23.16 $ 0.2 0.8 2,645,456 $ 14.25 $ 24.1 2.4 The aggregate intrinsic value in the table above represents the difference between the Company's closing stock price on December 31, 2021 and the exercise price of each SSAR and stock option, multiplied by the number of in-the-money awards. There was no unrecognized compensation expense related to SSARs at December 31, 2021. Unrecognized compensation expense related to stock options not yet exercisable at December 31, 2021 was $2.5 million. This cost is expected to be recognized over a weighted-average period of 1.1 years. Other information regarding the exercise of SSARs and stock options is listed below: Years Ended December 31, (in millions) 2021 2020 2019 SSARs Aggregate intrinsic value of SSARs exercised $ 0.1 $ — $ 0.4 Stock Options Cash received by Knowles for exercise of stock options $ 25.6 $ 1.8 $ 9.8 Aggregate intrinsic value of stock options exercised 6.6 0.4 2.7 Tax benefit from stock options exercised 1.2 — — RSUs The following table summarizes the Company's RSU activity for the year ended December 31, 2021: Share units Weighted-average grant date fair value Unvested at December 31, 2020 1,909,786 $ 16.14 Granted 1,159,374 20.59 Vested (1) (1,068,104) 15.81 Forfeited (222,417) 18.42 Unvested at December 31, 2021 1,778,639 $ 18.89 (1) The number of RSUs vested includes shares that the Company withheld on behalf of employees to satisfy statutory tax withholding requirements. RSUs vest based on the passage of time. Generally, RSUs have a three year vesting schedule and vest one-third on each of the first three anniversaries of the grant date. The fair value of RSUs vested during the year ended December 31, 2021 was $21.9 million. At December 31, 2021, $19.7 million of unrecognized compensation expense related to RSUs is expected to be recognized over a weighted-average period of 1.6 years. PSUs The Company grants PSUs to senior management. In each case, the awards will cliff vest three years following the grant date. PSUs will be settled in shares of the Company's common stock. Depending on the Company's overall performance relative to the applicable measures, the size of the PSU awards are subject to adjustment, up or down, resulting in awards at the end of the performance period that can range from 0% to 225% of target. The Company will ratably recognize the expense over the applicable service period for each grant of PSUs and adjust the expense for the expected achievement of performance conditions as appropriate. The fair value of PSUs is determined by using a Monte Carlo simulation. For the awards granted in February 2021, the number of PSUs that may be earned and vest is based on total shareholder return (“TSR”) relative to the component companies of the Russell 2000 Index over a three-year performance period. The COVID-19 pandemic brought on unique and unprecedented challenges to the Company, particularly in the hearing health and medtech markets. Many of the Company's executive compensation programs were affected, including outstanding PSU awards. Due to the impact of the COVID-19 pandemic on the Company’s overall business performance, effective February 8, 2021, the Company’s Compensation Committee approved certain modifications to PSUs granted in February 2018, 2019, and 2020. For the awards granted in February 2018 (the “2018 PSUs”), the number of PSUs that may be earned and vest was originally based on the Company’s revenues and stock price performance over a three-year performance period. The modified award was based on the Company’s revenues and stock price performance over three separate one-year performance periods to isolate the impact of the COVID-19 pandemic on the Company's fiscal 2020 performance. In addition, the performance periods corresponding to fiscal 2018 and 2019 were weighted at 25% each while the performance period corresponding to fiscal 2020 was weighted at 50%, given the impact of fiscal 2020 performance on shareholders. Service conditions were not modified. The modification of the 2018 PSUs affected nine employees and resulted in total incremental compensation expense of $3.9 million, which was recognized in the first quarter of 2021 as there was no remaining service period. In February 2021, the 2018 PSUs were converted from 329,092 PSUs to 190,544 shares of common stock based on achievement of the modified conditions. For the awards granted in February 2019 (the “2019 PSUs”), the number of PSUs that may be earned and vest was originally based on the Company's revenues and TSR relative to the component companies of the S&P Semiconductor Select Industry Index over a three-year performance period. The modified award is based on the Company’s revenues and TSR relative to the component companies of the S&P Semiconductor Select Industry Index over three separate one-year performance periods to isolate the impact of the COVID-19 pandemic on the Company's fiscal 2020 performance. Each period is weighted equally, as the Company expected to face challenges related to the COVID-19 pandemic in fiscal 2021. Service conditions were not modified. The modification of the 2019 PSUs affected eight employees and resulted in total incremental compensation expense of $2.4 million, which will be recognized over the remaining service period. Incremental compensation expense was subject to adjustment for the achievement of the performance condition based on fiscal 2021 revenues. For the awards granted in February 2020 (the “2020 PSUs”), the number of PSUs that may be earned and vest was originally based on TSR relative to the component companies of the S&P Semiconductor Select Industry Index over a three-year performance period. The modified award replaces the S&P Semiconductor Select Industry Index with the Russell 2000 Index. The Company is a member of the Russell 2000 Index, which represents a broader, more diversified index that better aligns with the Company's strategy. Service conditions were not modified. The modification of the 2020 PSUs affected eight employees and resulted in total incremental compensation expense of $4.7 million, which will be recognized over the remaining service period. The following table summarizes the Company's PSU activity for the year ended December 31, 2021: Share units Weighted-average grant date fair value Unvested at December 31, 2020 920,973 $ 16.04 Granted 293,874 28.49 Vested (1) (346,898) 14.13 Forfeited (101,483) 19.05 Unvested at December 31, 2021 766,466 $ 21.28 (1) The number of PSUs vested includes shares that the Company withheld on behalf of employees to satisfy statutory tax withholding requirements. The fair value of PSUs vested during the year ended December 31, 2021 was $3.9 million. At December 31, 2021, $10.0 million of unrecognized compensation expense related to PSUs is expected to be recognized over a weighted-average period of 1.2 years.

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Schedule of Plan Obligations and Funded Status	The following tables summarize the balance sheet impact, including the benefit obligations, assets, and funded status associated with the Company's four defined benefit plans for non-U.S. participants at December 31, 2021 and 2020. December 31, (in millions) 2021 2020 Change in benefit obligation: Benefit obligation at beginning of year $ 74.5 $ 64.1 Service cost 0.3 0.3 Interest cost 0.9 1.2 Benefits paid (1.6) (1.7) Actuarial (gain) loss (1) (3.8) 8.3 Settlements and curtailments — (0.2) Currency translation and other (0.8) 2.5 Benefit obligation at end of year 69.5 74.5 Change in plan assets: Fair value of plan assets at beginning of year 65.7 58.2 Actual return on plan assets 4.6 5.8 Company contributions 1.5 1.5 Benefits paid (1.6) (1.7) Settlements and curtailments — (0.2) Currency translation and other (0.9) 2.1 Fair value of plan assets at end of year 69.3 65.7 Funded status $ (0.2) $ (8.8) Amounts recognized in the Consolidated Balance Sheets consist of: Other assets and deferred charges $ 2.6 $ — Other liabilities (2.8) (8.8) Funded status $ (0.2) $ (8.8) Accumulated other comprehensive loss: Net actuarial losses $ 19.2 $ 25.6 Prior service cost 1.1 1.1 Deferred taxes (3.3) (4.8) Total accumulated other comprehensive loss, net of tax 17.0 21.9 Accumulated benefit obligation $ 68.4 $ 73.3
Schedule of Accumulated Benefit Obligations in Excess of Plan Assets	Pension plans with accumulated benefit obligations in excess of plan assets consisted of the following at December 31, 2021 and 2020: December 31, (in millions) 2021 2020 Accumulated benefit obligation $ 40.0 $ 43.0 Fair value of plan assets 37.8 34.8
Schedule of Net Periodic Benefit Costs	Components of the net periodic benefit cost (income) were as follows: Years Ended December 31, (in millions) 2021 2020 2019 Service cost $ 0.3 $ 0.3 $ 0.3 Interest cost 0.9 1.2 1.5 Expected return on plan assets (2.8) (2.4) (2.4) Amortization of prior service cost — 0.1 0.1 Amortization of recognized actuarial loss 0.8 0.5 0.4 Other — — 0.1 Total net periodic benefit cost (income) $ (0.8) $ (0.3) $ —
Schedule of Assumptions Used	The assumptions used in determining the benefit obligations were as follows: December 31, 2021 2020 Discount rate Philippines 5.25 % 4.00 % Taiwan 0.75 % 0.25 % United Kingdom 1.84 % 1.28 % Weighted-average 1.83 % 1.27 % Average wage increase Philippines 4.00 % 4.00 % Taiwan 4.00 % 4.00 % United Kingdom 4.65 % 4.20 % Weighted-average 4.59 % 4.18 % The assumptions used in determining the net periodic benefit cost (income) were as follows: Years Ended December 31, 2021 2020 2019 Discount rate Philippines 4.00 % 5.00 % 8.25 % Taiwan 0.25 % 0.75 % 1.25 % United Kingdom 1.28 % 2.00 % 2.80 % Weighted-average 1.27 % 1.97 % 2.78 % Average wage increase Philippines 4.00 % 5.00 % 6.00 % Taiwan 4.00 % 4.00 % 4.25 % United Kingdom 4.20 % 4.25 % 4.40 % Weighted-average 4.18 % 4.24 % 4.41 % Expected return on plan assets Taiwan 3.50 % 3.75 % 2.00 % United Kingdom 4.34 % 4.35 % 4.82 % Weighted-average 4.32 % 4.33 % 4.72 %
Fair Value of Plan Assets by Asset Category	The fair values of plan assets by asset category within the ASC 820 hierarchy were as follows at December 31, 2021 and 2020: December 31, 2021 December 31, 2020 (in millions) Level 1 Level 2 Level 3 Total Fair Value Level 1 Level 2 Level 3 Total Fair Value Asset category: Fixed income investments $ 3.5 $ 26.1 $ — $ 29.6 $ 3.4 $ 24.9 $ — $ 28.3 Common stock funds — 18.9 — 18.9 — 18.9 — 18.9 Real estate funds — 5.5 — 5.5 — 5.0 — 5.0 Cash and equivalents 0.5 — — 0.5 0.3 — — 0.3 Other 9.0 5.8 — 14.8 7.9 5.3 — 13.2 Total $ 13.0 $ 56.3 $ — $ 69.3 $ 11.6 $ 54.1 $ — $ 65.7
Schedule of Expected Benefit Payments	Estimated future benefit payments to retirees, which reflect expected future service, are as follows: (in millions) 2022 $ 2.1 2023 1.9 2024 2.1 2025 2.6 2026 2.6 2027-2031 14.3

Other Comprehensive (Loss) Ea_2

Other Comprehensive (Loss) Earnings (Tables)	12 Months Ended
	Dec. 31, 2021
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Amounts Recognized in Other Comprehensive Income	The amounts recognized in other comprehensive earnings (loss) were as follows: Year Ended December 31, 2021 (in millions) Pre-tax Tax Net of tax Foreign currency translation $ (3.6) $ — $ (3.6) Employee benefit plans 6.6 (1.6) 5.0 Changes in fair value of cash flow hedges (1.6) 0.3 (1.3) Total other comprehensive earnings $ 1.4 $ (1.3) $ 0.1 Year Ended December 31, 2020 (in millions) Pre-tax Tax Net of tax Foreign currency translation $ 13.8 $ — $ 13.8 Employee benefit plans (4.4) 1.0 (3.4) Changes in fair value of cash flow hedges 1.4 (0.3) 1.1 Total other comprehensive earnings $ 10.8 $ 0.7 $ 11.5 Year Ended December 31, 2019 (in millions) Pre-tax Tax Net of tax Foreign currency translation $ 1.3 $ — $ 1.3 Employee benefit plans (3.2) — (3.2) Changes in fair value of cash flow hedges 1.1 (0.2) 0.9 Total other comprehensive loss $ (0.8) $ (0.2) $ (1.0)
Schedule of Components of Accumulated Other Comprehensive Income (Loss)	The following table summarizes the changes in balances of each component of accumulated other comprehensive loss, net of tax during the years ended December 31, 2021 and 2020: (in millions) Cash flow hedges Employee benefit plans Cumulative foreign currency translation adjustments Total Balance at January 1, 2020 $ 0.5 $ (18.7) $ (93.8) $ (112.0) Other comprehensive earnings (loss), net of tax 1.1 (3.4) 13.8 11.5 Balance at December 31, 2020 1.6 (22.1) (80.0) (100.5) Other comprehensive (loss) earnings, net of tax (1.3) 5.0 (3.6) 0.1 Balance at December 31, 2021 $ 0.3 $ (17.1) $ (83.6) $ (100.4) The following table summarizes the amounts reclassified from accumulated other comprehensive loss to earnings: Years Ended December 31, (in millions) Statement of Earnings Line 2021 2020 2019 Pension and post-retirement benefit plans: Amortization or settlement of actuarial losses and prior service costs Other (income) expense, net $ 0.9 $ 0.7 $ 0.6 Tax (Benefit from) provision for income taxes (0.2) (0.1) (0.1) Net of tax $ 0.7 $ 0.6 $ 0.5 Cash flow hedges: Net (gains) losses reclassified into earnings Cost of goods sold $ (2.1) $ (1.2) $ 0.9 Tax (Benefit from) provision for income taxes 0.5 0.3 (0.2) Net of tax $ (1.6) $ (0.9) $ 0.7

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2021
Segment Reporting [Abstract]
Revenue and Earnings from continuing operations by market segment	Years Ended December 31, (in millions) 2021 2020 2019 Revenues: Audio $ 667.0 $ 591.2 $ 682.8 Precision Devices 201.1 173.1 172.0 Total revenues $ 868.1 $ 764.3 $ 854.8 Earnings from continuing operations before interest and income taxes: Audio $ 137.0 $ 44.9 $ 107.3 Precision Devices 43.7 31.7 30.4 Total segments 180.7 76.6 137.7 Corporate expense / other 61.9 48.9 56.9 Interest expense, net 14.2 16.4 14.5 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Depreciation and amortization: Audio $ 46.2 $ 47.0 $ 41.3 Precision Devices 13.3 10.5 9.9 Corporate 3.0 3.1 3.2 Total $ 62.5 $ 60.6 $ 54.4 Capital expenditures: Audio $ 40.8 $ 21.9 $ 24.0 Precision Devices 5.6 9.6 16.5 Corporate 2.2 0.4 0.7 Total $ 48.6 $ 31.9 $ 41.2 Research and development: Audio $ 81.8 $ 84.6 $ 90.8 Precision Devices 10.5 6.7 5.8 Corporate 0.5 1.6 0.2 Total $ 92.8 $ 92.9 $ 96.8 Information regarding assets of the Company's reportable segments: Total Assets December 31, (in millions) 2021 2020 Audio $ 1,467.1 $ 1,470.4 Precision Devices 260.4 179.2 Corporate / eliminations 4.1 5.3 Total $ 1,731.6 $ 1,654.9
Revenue from External Customers by Geographic Areas	The following table details revenues by geographic location. Revenues are attributed to regions based on the location of the Company's direct customer, which in some instances is an intermediary and not necessarily the end user. Long-lived assets are comprised of net property, plant, and equipment and operating lease right-of-use assets. These assets have been classified based on the geographic location of where they reside. The Company's businesses are based primarily in Asia, North America, and Europe. Revenues Long-Lived Assets Years Ended December 31, December 31, (in millions) 2021 2020 2019 2021 2020 Asia $ 611.5 $ 559.6 $ 614.7 $ 149.5 $ 140.5 United States 153.2 116.7 130.4 64.6 69.8 Europe 93.5 80.0 97.4 3.1 3.3 Other Americas 5.5 3.7 6.3 1.0 1.2 Other 4.4 4.3 6.0 — — Total $ 868.1 $ 764.3 $ 854.8 $ 218.2 $ 214.8

Earnings per Share (Tables)

Earnings per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Reconciliation of information used in computing basic and diluted earnings per share	Basic and diluted earnings per share were computed as follows: Years Ended December 31, (in millions, except per share amounts) 2021 2020 2019 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Earnings (loss) from discontinued operations, net 0.2 3.7 (0.6) Net earnings $ 150.4 $ 6.6 $ 49.1 Basic earnings (loss) per common share: Earnings from continuing operations $ 1.63 $ 0.03 $ 0.55 Earnings (loss) from discontinued operations, net — 0.04 (0.01) Net earnings $ 1.63 $ 0.07 $ 0.54 Weighted-average shares outstanding 92.3 91.7 91.2 Diluted earnings (loss) per common share: Earnings from continuing operations $ 1.59 $ 0.03 $ 0.53 Earnings (loss) from discontinued operations, net — 0.04 — Net earnings $ 1.59 $ 0.07 $ 0.53 Diluted weighted-average shares outstanding 94.7 92.9 93.4

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) $ in Millions	Jul. 07, 2016USD ($)	Dec. 31, 2021USD ($)segmentsreporting_unit	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Accounting Policies [Line Items]
Revenue Recognition, Sales Discounts and Rebates		$ 5	$ 4.2	$ 4.7
Operating Lease, Liability		26.1
Operating Lease, Right-of-Use Asset		$ 17.4	23.3
Goodwill and Intangible Assets [Abstract]
Number of Reporting Units | reporting_unit		3
Goodwill		$ 941.3	910	909.9
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		0	0	0
Property, Plant and Equipment [Abstract]
Total impairment charges		$ 4	7.6	0
Revenue Recognition [Abstract]
Number of reportable segments | segments		2
Document Fiscal Year Focus		2021
Revenue Recognition, Sales Returns, Reserve for Sales Returns		$ 4.3	5.4	6.6
Increase (Decrease) in Contract Receivables, Net		137.7	123.8
Investments		6.4	2.5
Noncash Investing and Financing Items [Abstract]
Purchases of property and equipment included in accounts payable		$ 5.4	2	4.7
Minimum
Goodwill and Intangible Assets [Abstract]
Percentage of fair value in excess of carrying amount		35.00%
Buildings and improvements | Maximum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		31 years 6 months
Buildings and improvements | Minimum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		5 years
Machinery and equipment | Maximum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		7 years
Machinery and equipment | Minimum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		1 year 6 months
Furniture and fixtures | Maximum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		5 years
Furniture and fixtures | Minimum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		2 years
Vehicles
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		3 years
Software and software development costs | Maximum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		5 years
Software and software development costs | Minimum
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life		3 years
Speaker and Receiver Product Line | Discontinued Operations, Disposed of by Sale [Member]
Accounting Policies [Line Items]
Proceeds from Divestiture of Businesses	$ 40.6
Precision Devices
Goodwill and Intangible Assets [Abstract]
Goodwill		$ 62.5	31.2	31.2
Precision Devices | Timing Device Business [Member] | Discontinued Operations, Disposed of by Sale [Member]
Accounting Policies [Line Items]
Proceeds from Divestiture of Businesses				135.1
Audio
Goodwill and Intangible Assets [Abstract]
Goodwill		878.8	$ 878.8	$ 878.7
Mobile Consumer Electronics [Member]
Goodwill and Intangible Assets [Abstract]
Goodwill		741
Hearing Health Technologies [Member]
Goodwill and Intangible Assets [Abstract]
Goodwill		137.8
Precision Devices
Goodwill and Intangible Assets [Abstract]
Goodwill		$ 62.5

Disposed and Discontinued Ope_3

Disposed and Discontinued Operations (Details) - USD ($) $ in Millions	Jul. 07, 2016	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Nov. 28, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Liabilities		$ 0	$ 0.6
Total assets		1,731.6	1,654.9
Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Other Liabilities, Noncurrent			0.6
Disposal Group, Including Discontinued Operation, Revenue		0	0	$ 0
Disposal Group, Including Discontinued Operation, Operating Expense		0	0	0
Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax		0	0	0
Discontinued Operation, Tax Effect of Discontinued Operation		(0.2)	(3.7)	0.6
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax		0.2	3.7	(0.6)
Disposal Group, Including Discontinued Operation, Liabilities			$ 0.6
Liabilities		0
Total assets		$ 0
Timing Device Business [Member] | Precision Devices | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of business				$ 135.1
Disposal Group, Including Discontinued Operation, Consideration					$ 130
Speaker and Receiver Product Line | Discontinued Operations, Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of business	$ 40.6
Disposal Group, Including Discontinued Operation, Consideration	$ 45

Acquisition Acquisition (Detail

Acquisition Acquisition (Details) - USD ($) $ / shares in Units, $ in Millions	May 03, 2021	Dec. 20, 2019	Jan. 03, 2019	Jan. 19, 2018	Dec. 31, 2021	Dec. 31, 2021	Sep. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Document Fiscal Year Focus								2021
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent								$ 150.2	$ 2.9	$ 49.7
Revenues								868.1	764.3	854.8
Net earnings								150.4	6.6	49.1
Goodwill					$ 941.3	$ 941.3		$ 941.3	$ 910	$ 909.9
Income (Loss) from Continuing Operations, Per Basic Share								$ 1.63	$ 0.03	$ 0.55
Income (Loss) from Continuing Operations, Per Diluted Share								$ 1.59	$ 0.03	$ 0.53
ASIC Design Business [Member]
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Net Income (Loss)										$ 40.7
Payments to Acquire Businesses, Gross		$ 57.9
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		$ 0.1
Business Acquisition, Pro Forma Earnings Per Share, Basic										$ 0.45
Business Acquisition, Pro Forma Earnings Per Share, Diluted										$ 0.44
DITF Interconnect Technology, Inc. [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 11.1
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual							$ 8.9
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual							$ 0.3
Compex Corporation [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross				$ 16
Business Combination, Consideration Transferred				18.7
Integrated Microwave Corporation
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 80.7
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	8.3
Goodwill	31.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities	(1.2)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	80.7
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual						11.2
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual						$ 0.3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents	2.2
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables	3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory	2.6
In Process Research and Development [Member]
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life					9 years
Customer relationships | Integrated Microwave Corporation
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life						8 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	27.7
Developed technology (1) | Integrated Microwave Corporation
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life						10 years
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	5.2
Trademarks [Member] | Integrated Microwave Corporation
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 1.6
Precision Devices
Business Acquisition [Line Items]
Goodwill					$ 62.5	$ 62.5		$ 62.5	$ 31.2	$ 31.2
Other liabilities | Compex Corporation [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross				$ 1

Acquisition Acquisition - Selec

Acquisition Acquisition - Selected Unaudited Pro-forma Combined Statement of Earnings (Details) - USD ($) $ / shares in Units, $ in Millions	May 03, 2021	Dec. 20, 2019	Jan. 19, 2018	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition, Pro Forma Information [Abstract]
Revenues					$ 868.1	$ 764.3	$ 854.8
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent					$ 150.2	$ 2.9	$ 49.7
Income (Loss) from Continuing Operations, Per Basic Share					$ 1.63	$ 0.03	$ 0.55
Income (Loss) from Continuing Operations, Per Diluted Share					$ 1.59	$ 0.03	$ 0.53
ASIC Design Business [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross		$ 57.9
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		$ 0.1
Business Acquisition, Pro Forma Information [Abstract]
Business Acquisition, Pro Forma Net Income (Loss)							$ 40.7
Business Acquisition, Pro Forma Earnings Per Share, Basic							$ 0.45
Business Acquisition, Pro Forma Earnings Per Share, Diluted							$ 0.44
Compex Corporation [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 16
Business Acquisition, Pro Forma Information [Abstract]
Business Combination, Consideration Transferred			18.7
Integrated Microwave Corporation
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	$ 80.7
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual				$ 11.2
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual				$ 0.3
Other liabilities | Compex Corporation [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross			$ 1

Impairments (Details)

Impairments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Asset Impairment Charges [Abstract]
Total impairment charges			$ 4	$ 7.6	$ 0
Operating Lease, Liability		$ 26.1	26.1
Operating Lease, Right-of-Use Asset		17.4	17.4	23.3
Total impairment charges			4	7.6	$ 0
Operating Lease, Right-of-Use Asset		17.4	17.4	23.3
Operating Lease, Liability		26.1	$ 26.1
Mountain View California
Asset Impairment Charges [Abstract]
Total impairment charges		3.2		5.4
Total impairment charges		$ 3.2		5.4
Santa Clara California
Asset Impairment Charges [Abstract]
Total impairment charges	$ 0.8			2.2
Operating Lease, Liability						$ 4
Operating Lease, Right-of-Use Asset						2.4
Total impairment charges	$ 0.8			$ 2.2
Operating Lease, Right-of-Use Asset						2.4
Operating Lease, Liability						$ 4

Inventories (Details)

Inventories (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Inventory, Net [Abstract]
Raw materials	$ 89.6	$ 89.7
Work in progress	33.6	31
Finished goods	66.7	48.4
Subtotal	189.9	169.1
Less reserves	(36.8)	(39)
Total	$ 153.1	$ 130.1

Property, Plant and Equipment_3

Property, Plant and Equipment, net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 707.2	$ 682.7
Less Accumulated depreciation	(506.4)	(491.2)
Property, plant and equipment, net	200.8	191.5
Depreciation	46.6	47.6	$ 47.4
Land
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	12.9	8
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	119.3	111.9
Machinery, equipment, and other
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 575	$ 562.8

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Roll Forward]
Beginning balance	$ 910	$ 909.9
Acquisitions	31.3
Goodwill, Foreign Currency Translation Gain (Loss)		0.1
Ending balance	941.3	910
Audio
Goodwill [Roll Forward]
Beginning balance	878.8	878.7
Acquisitions	0
Goodwill, Foreign Currency Translation Gain (Loss)		0.1
Ending balance	878.8	878.8
Precision Devices
Goodwill [Roll Forward]
Beginning balance	31.2	31.2
Acquisitions	31.3
Goodwill, Foreign Currency Translation Gain (Loss)		0
Ending balance	$ 62.5	$ 31.2

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Intangible Assets and Amortization Expense (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		6 years 2 months 12 days
Finite-Lived Intangible Assets, Gross	$ 86.2	$ 86.2	$ 92.1
Accumulated Amortization	20.9	20.9	49.1
Indefinite-lived Intangible Assets (Excluding Goodwill)	32	32	35.7
Intangible Assets, Net	97.3	97.3	78.7
Selling and Administrative Expenses
Finite-Lived Intangible Assets [Line Items]
Amortization Expense		$ 15.9	13	$ 7
Trademarks
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years 4 months 24 days
Finite-Lived Intangible Assets, Gross	2	$ 2	1
Accumulated Amortization	0.6	0.6	0.4
Patents
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	0	0	40.8
Accumulated Amortization	0	$ 0	36.1
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years
Finite-Lived Intangible Assets, Gross	36.4	$ 36.4	12
Accumulated Amortization	5.9	$ 5.9	5.2
Developed technology (1)
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		5 years 3 months 18 days
Finite-Lived Intangible Assets, Gross	45.4	$ 45.4	36.5
Accumulated Amortization	13.2	$ 13.2	6.7
Other
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		5 years 1 month 6 days
Finite-Lived Intangible Assets, Gross	2.4	$ 2.4	1.8
Accumulated Amortization	$ 1.2	1.2	0.7
In Process Research and Development [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	9 years
Unamortized intangible assets:
Finite-Lived Intangible Asset, Useful Life	9 years
In Process Research and Development [Member]
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 0	0	3.7
Trademarks
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Assets (Excluding Goodwill)	$ 32	$ 32	$ 32

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Unamortized intangible assets:
Gross Carrying Amount	$ 32	$ 35.7
Trademarks
Unamortized intangible assets:
Gross Carrying Amount	32	32
In Process Research and Development [Member]
Unamortized intangible assets:
Gross Carrying Amount	$ 0	$ 3.7

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Future Amortization Expense (Details) $ in Millions	Dec. 31, 2021USD ($)
Future Amortization Expense [Abstract]
2018	$ 12.2
2019	11.6
2020	11.6
2021	11.2
2022	$ 5.3

Leases (Details)

Leases (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	$ 2.7	$ 2.6
Finance Lease, Liability, Noncurrent	3.6	$ 5.5
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	12.1
Finance Lease, Liability, Payments, Remainder of Fiscal Year	$ 2.7
Operating Lease, Weighted Average Remaining Lease Term	3 years 1 month 6 days	3 years 8 months 12 days
Operating Lease, Payments	$ 10.2	$ 9.6	$ 10.4
Operating Lease, Cost	9.9	9.9	9.8
Finance Lease, Right-of-Use Asset, Amortization	2.3	2.1	2.2
Finance Lease, Interest Expense	0.4	0.5	0.2
Sublease Income	(3)	(3)	(2.9)
Lease, Cost	9.6	9.5	9.3
Finance Lease, Liability	6.3	8.1
Finance Lease, Interest Payment on Liability	0.4	0.5	0.6
Finance Lease, Principal Payments	2.3	2	1.7
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	6.5	2.2	2.6
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	$ 0.3	$ 0.1	$ 0.3
Finance Lease, Weighted Average Remaining Lease Term	3 years 1 month 6 days	4 years 1 month 6 days
Operating Lease, Weighted Average Discount Rate, Percent	3.80%	4.20%
Finance Lease, Weighted Average Discount Rate, Percent	5.40%	5.50%
Lessee, Operating Lease, Liability, Payments, Due Year Two	$ 8.5
Finance Lease, Liability, Payments, Due Year Two	2.7
Lessee, Operating Lease, Liability, Payments, Due Year Three	3.9
Finance Lease, Liability, Payments, Due Year Three	1.4
Lessee, Operating Lease, Liability, Payments, Due Year Four	2
Finance Lease, Liability, Payments, Due Year Four	0
Lessee, Operating Lease, Liability, Payments, Due Year Five	0.7
Finance Lease, Liability, Payments, Due Year Five	0
Lessee, Operating Lease, Liability, Payments, Due after Year Five	0.2
Finance Lease, Liability, Payments, Due after Year Five	0
Lessee, Operating Lease, Liability, Payments, Due	27.4
Finance Lease, Liability, Payment, Due	6.8
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(1.3)
Finance Lease, Liability, Undiscounted Excess Amount	(0.5)
Operating Lease, Liability	26.1
Property, Plant and Equipment
Finance Lease, Right-of-Use Asset	8.1	$ 10.2
Finance Lease, Right-of-Use Asset	$ 8.1	$ 10.2
Maximum [Member]
Lessee, Operating Lease, Term of Contract	6 years
Lessor, Operating Lease, Renewal Term	6 years
Minimum [Member]
Lessee, Operating Lease, Term of Contract	1 year
Lessee Operating and Finance Leases Options to Terminate Leases Term	1 year

Accrued Expenses and Other Li_3

Accrued Expenses and Other Liabilities - Schedule of Accrued Expenses (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Accrued Liabilities and Other Liabilities [Abstract]
Restructuring and exit costs	$ 0.4	$ 2.4
Sales volume rebates	$ 4.9	$ 3.5
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current	Other Liabilities, Current
Accrued taxes other than income taxes	$ 4.2	$ 3.7
Warranty	0.5	0.4
Accrued Insurance	1.7	1.7
Hedging liability	0.2	0
Other	4.8	4.3
Other accrued expenses	19.4	18.6
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	$ 2.7	$ 2.6

Accrued Expenses and Other Li_4

Accrued Expenses and Other Liabilities - Schedule of Other Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2020
Accrued Liabilities and Other Liabilities [Abstract]
Finance Lease, Liability, Noncurrent		$ 3.6	$ 5.5
Total		20.6	32.8
Operating Lease, Liability		26.1
Finance Lease, Liability, Noncurrent		$ 3.6	$ 5.5
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration]		Total	Total
Total impairment charges		$ 4	$ 7.6	$ 0
Santa Clara California
Accrued Liabilities and Other Liabilities [Abstract]
Operating Lease, Liability					$ 4
Total impairment charges	$ 0.8		2.2
Other liabilities
Accrued Liabilities and Other Liabilities [Abstract]
Deferred compensation, including defined benefit plans		13.9	20.5
Unrecognized tax benefits		2	1.5
Restructuring and exit costs		0	0.2
Other Sundry Liabilities, Noncurrent		1.1	5.1
Deferred compensation, including defined benefit plans		13.9	20.5
Unrecognized tax benefits		2	1.5
Restructuring and exit costs		0	0.2
Other Sundry Liabilities, Noncurrent		$ 1.1	$ 5.1

Accrued Expenses and Other Li_5

Accrued Expenses and Other Liabilities Accrued Expenses and Other Liabilities - Product Warrant Accrual Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Warranty Accrual [Roll Forward]
Beginning balance, January 1	$ 0.4	$ 0.9	$ 0.5
Provision for warranties	1	3.8	3.8
Settlements made	(0.9)	(4.3)	(3.4)
Ending balance, December 31	0.5	$ 0.4	$ 0.9
Operating Lease, Liability	$ 26.1

Restructuring and Related Act_3

Restructuring and Related Activities - Costs Recognized and Remaining Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0.5	$ 10.6	$ 6
Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.5	10	4.3
Cost of Goods Sold, Restructuring Charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0	2.3	1.7
Severance Pay and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0.5	9.4	6
Facility Closing [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ 1.2	$ 0

Restructuring and Related Act_4

Restructuring and Related Activities - Restructuring Activities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 0.5	$ 12.3	$ 6
Document Fiscal Year Focus	2021
Restructuring Reserve [Roll Forward]
Beginning balance	$ 2.6	1.4	0.8
Restructuring charges	0.5	10.6	6
Payments	(2.7)	(9.4)	(5.4)
Ending balance	0.4	2.6	1.4
Intelligent Audio
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		8.3
Severance Pay and Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	1.9	1.4	0.8
Restructuring charges	0.5	9.4	6
Payments	(2)	(8.9)	(5.4)
Ending balance	0.4	1.9	1.4
Facility Closing [Member]
Restructuring Reserve [Roll Forward]
Beginning balance	0.7	0	0
Restructuring charges	0	1.2	0
Payments	(0.7)	(0.5)	0
Ending balance	0	0.7	0
Corporate, Non-Segment [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0	1.7	0.4
Audio
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0.4	10.5	4.8
Precision Devices
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	0.1	0.1	0.8
Restructuring Charges [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges	0.5	10	4.3
Cost of Goods Sold, Restructuring Charges [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges	$ 0	2.3	$ 1.7
Cost of Goods Sold, Restructuring Charges [Member] | Severance Pay and Benefits | Intelligent Audio
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		5.4
Cost of Goods Sold, Restructuring Charges [Member] | Severance Pay and Benefits | Audio
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		4
Cost of Goods Sold, Restructuring Charges [Member] | Facility Closing [Member] | Intelligent Audio
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		1.7
Cost of Goods Sold, Restructuring Charges [Member] | Contract Termination | Intelligent Audio
Restructuring Cost and Reserve [Line Items]
Restructuring Charges		$ 1.2

Restructuring and Related Act_5

Restructuring and Related Activities - Balance Sheet Location (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 0.4	$ 2.6	$ 1.4	$ 0.8
Other accrued expenses
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	0.4	2.4
Other liabilities
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 0	$ 0.2

Hedging Transactions and Deri_2

Hedging Transactions and Derivative Instruments - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Document Fiscal Year Focus	2021
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax	$ (0.2)	$ (0.6)	$ 0
Foreign Currency Gain (Loss) [Member] | Not Designated as Hedging Instrument, Economic Hedge [Member] | Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	93.2	77.1
Foreign Exchange Forward [Member] | Cash Flow Hedging | Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	59.4	69
Foreign Exchange Contract [Member] | Cash flow hedges
Derivative [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	0.5	2.6	0.2
Foreign Exchange Contract [Member] | Cash Flow Hedging | Designated as Hedging Instrument | Other expense (income), net
Derivative [Line Items]
Gain (loss) on derivatives	$ 0	$ 0	$ 0

Hedging Transactions and Deri_3

Hedging Transactions and Derivative Instruments - Fair Value of Derivative Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Cost of goods sold	$ 508.6	$ 490.8	$ 525.1
Interest Revenue (Expense), Net	(14.2)	(16.4)	(14.5)
Other Nonoperating Income (Expense)	3	(1.5)	(0.4)
Fair value	$ (0.2)	0
Document Fiscal Year Focus	2021
Cash Flow Hedging | Designated as Hedging Instrument | Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 59.4	69
Cash Flow Hedging | Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets [Member] | Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0.7	2.1
Cash Flow Hedging | Designated as Hedging Instrument | Other accrued expenses | Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Fair value	0.2	0
Not Designated as Hedging Instrument, Economic Hedge [Member] | Not Designated as Hedging Instrument | Foreign Currency Gain (Loss) [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	93.2	77.1
Not Designated as Hedging Instrument, Economic Hedge [Member] | Not Designated as Hedging Instrument | Prepaid Expenses and Other Current Assets [Member] | Foreign Currency Economic Hedge
Derivatives, Fair Value [Line Items]
Fair value	(0.3)	(0.4)
Cost of Sales | Cash Flow Hedging | Designated as Hedging Instrument | Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) on derivatives	2.1	1.2	(0.9)
Cost of Sales | Not Designated as Hedging Instrument, Economic Hedge [Member] | Not Designated as Hedging Instrument | Foreign Currency Economic Hedge
Derivatives, Fair Value [Line Items]
Gain (loss) on derivatives	0	0	0
Other expense (income), net | Cash Flow Hedging | Designated as Hedging Instrument | Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Gain (loss) on derivatives	0	0	0
Other expense (income), net | Not Designated as Hedging Instrument, Economic Hedge [Member] | Not Designated as Hedging Instrument | Foreign Currency Economic Hedge
Derivatives, Fair Value [Line Items]
Gain (loss) on derivatives	$ (1.4)	$ (2.9)	$ (0.9)

Hedging Transaction and Derivat

Hedging Transaction and Derivative Instruments - Fair Value of Derivatives Qualifying as Hedging Instrument (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Foreign Exchange Contract [Member] | Designated as Hedging Instrument | Cash Flow Hedging | Other expense (income), net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	$ 0	$ 0	$ 0
Foreign Exchange Contract [Member] | Designated as Hedging Instrument | Cash Flow Hedging | Cost of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	2.1	1.2	(0.9)
Foreign Currency Economic Hedge | Not Designated as Hedging Instrument | Not Designated as Hedging Instrument, Economic Hedge [Member] | Other expense (income), net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	(1.4)	(2.9)	(0.9)
Foreign Currency Economic Hedge | Not Designated as Hedging Instrument | Not Designated as Hedging Instrument, Economic Hedge [Member] | Cost of Sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	$ 0	$ 0	$ 0

Borrowings and Lines of Credi_2

Borrowings and Lines of Credit - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	May 04, 2016
Debt Instrument [Line Items]
Document Fiscal Year Focus	2021
Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year	$ 0
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	70
Long-term borrowings [Abstract]
Long-term debt	70	$ 165.1
Less: current maturities	0	165.1
Long-term debt (noncurrent)	70	0
Convertible Debt | Convertible Notes Due Twenty Twenty One [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Four	0
Long-term borrowings [Abstract]
Convertible Debt	0	165.1
Debt instrument, face amount		172.5		$ 172.5
Debt Instrument, Interest Rate, Stated Percentage				3.25%
Debt Instrument, Fair Value Disclosure		196.5
Debt instrument, convertible, carrying amount of equity component				$ 29.9
Line of Credit | Credit Facility Due October 11, 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Five	0
Long-term borrowings [Abstract]
Long-term Line of Credit	$ 70
Line of Credit | Term Loan and Revolving Credit Facility Due January 2019 [Member]
Long-term borrowings [Abstract]
Long-term Line of Credit		$ 0
London Interbank Offered Rate (LIBOR) [Member] | Credit Facilities [Member]
Long-term borrowings [Abstract]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	2.25%	2.20%	3.98%
Weighted Average [Member] | Credit Facilities [Member]
Long-term borrowings [Abstract]
Line of Credit Facility, Commitment Fee Percentage	0.26%	0.26%	0.23%

Borrowings and Lines of Credi_3

Borrowings and Lines of Credit - Schedule of Interest Expense and Interest Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Document Fiscal Year Focus	2021
Interest expense	$ 14.4	$ 17.1	$ 15.3
Interest income	(0.2)	(0.7)	(0.8)
Interest Revenue (Expense), Net	14.2	16.4	14.5
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Two	0
Long-term Debt, Maturities, Repayments of Principal in Year Three	70
Convertible Debt | Convertible Notes Due Twenty Twenty One [Member]
Debt Instrument [Line Items]
Interest Expense, Debt, Excluding Amortization	4.7	5.6	5.6
Interest Expense, Debt	12.1	$ 13.9	$ 13.3
Maturities of Long-term Debt [Abstract]
Long-term Debt, Maturities, Repayments of Principal in Year Four	$ 0

Borrowings and Lines of Credi_4

Borrowings and Lines of Credit Borrowings and Lines of Credit - Narrative (Details)	12 Months Ended
	Dec. 31, 2021USD ($)$ / shares	Dec. 31, 2020USD ($)$ / shares	Dec. 31, 2019USD ($)$ / shares	Sep. 04, 2020USD ($)	Oct. 11, 2017USD ($)	May 04, 2016USD ($)$ / shares
Debt Instrument [Line Items]
Long-term debt	$ 70,000,000	$ 165,100,000
Long-term Debt, Current Maturities	$ 0	$ 165,100,000
Debt Instrument, Convertible, Conversion Ratio	54.2741
Debt Instrument, Convertible, Conversion Price | $ / shares	$ 18.4250
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share | $ / shares	$ 0	$ 0.04	$ (0.01)
Long-term debt	$ 70,000,000	$ 0
Net deferred tax asset	$ 78,100,000	17,900,000
Document Fiscal Year Focus	2021
Convertible Notes Due Twenty Twenty One [Member] | Convertible Debt
Debt Instrument [Line Items]
Debt instrument, face amount		172,500,000				$ 172,500,000
Debt instrument, convertible, carrying amount of equity component						$ 29,900,000
Interest Expense, Debt, Excluding Amortization	$ 4,700,000	5,600,000	$ 5,600,000
Amortization of Debt Issuance Costs	800,000	900,000	900,000
Amortization of Debt Discount (Premium)	6,600,000	7,400,000	6,800,000
Debt Instrument, Unamortized Discount		(7,400,000)
Convertible Notes Payable		165,100,000
Convertible Notes Payable, Current		165,100,000
Convertible Notes Payable, Noncurrent		0
Debt Instrument, Fair Value Disclosure		196,500,000
Payments for Hedge, Financing Activities	44,500,000
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares						$ 21.1050
Proceeds from issuance of warrants	39,100,000
Interest Expense, Debt	12,100,000	13,900,000	$ 13,300,000
Credit Facility Due October 11, 2022 [Member] | Line of Credit
Debt Instrument [Line Items]
Long-term Line of Credit	$ 70,000,000
Term Loan and Revolving Credit Facility Due January 2019 [Member] | Line of Credit
Debt Instrument [Line Items]
Long-term Line of Credit		0
Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Debt covenant, EBITDA to interest ratio	3.25
Debt Instrument, Covenant, Debt to EBITDA, Maximum	3.75
Debt Instrument, Covenant, Senior Secured Leverage Ratio, Maximum	3.25
Line of credit facility, maximum borrowing capacity				$ 400,000,000
Credit Facility due January 2, 2024 [Member] | Line of Credit
Debt Instrument [Line Items]
Long-term Line of Credit	$ 70,000,000	0
Line of Credit, Current	$ 0	$ 0
London Interbank Offered Rate (LIBOR) | Credit Facilities
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate, at Point in Time	2.25%	2.20%	3.98%
Minimum | Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Minimum | Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.225%
Minimum | London Interbank Offered Rate (LIBOR) | Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%
Maximum | Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	1.50%
Maximum | Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Line of credit facility, accordion feature, increase limit					$ 200,000,000
Line of Credit Facility, Commitment Fee Percentage	0.375%
Maximum | London Interbank Offered Rate (LIBOR) | Credit Facility due January 2, 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	2.50%
Weighted Average | Credit Facilities
Debt Instrument [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.26%	0.26%	0.23%

Income Taxes - Income before Ta

Income Taxes - Income before Tax, Domestic and Foreign (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Income Tax Penalties Expense		$ 0	$ 0	$ 0
Document Fiscal Year Focus		2021
Components of Earnings before Income Tax [Abstract]
Domestic		$ 15.5	(26.2)	(48.3)
Foreign		89.1	37.5	114.6
(Loss) earnings before income taxes	[1]	104.6	11.3	66.3
Unrecognized Tax Benefits, Interest on Income Taxes Expense		0	0	0
Unrecognized Tax Benefits, Income Tax Penalties Accrued		0.3	$ 0.3	$ 0.3
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		$ 2
[1]	Years Ended December 31, (in millions) 2021 2020 2019 Revenues: Audio $ 667.0 $ 591.2 $ 682.8 Precision Devices 201.1 173.1 172.0 Total revenues $ 868.1 $ 764.3 $ 854.8 Earnings from continuing operations before interest and income taxes: Audio $ 137.0 $ 44.9 $ 107.3 Precision Devices 43.7 31.7 30.4 Total segments 180.7 76.6 137.7 Corporate expense / other 61.9 48.9 56.9 Interest expense, net 14.2 16.4 14.5 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Depreciation and amortization: Audio $ 46.2 $ 47.0 $ 41.3 Precision Devices 13.3 10.5 9.9 Corporate 3.0 3.1 3.2 Total $ 62.5 $ 60.6 $ 54.4 Capital expenditures: Audio $ 40.8 $ 21.9 $ 24.0 Precision Devices 5.6 9.6 16.5 Corporate 2.2 0.4 0.7 Total $ 48.6 $ 31.9 $ 41.2 Research and development: Audio $ 81.8 $ 84.6 $ 90.8 Precision Devices 10.5 6.7 5.8 Corporate 0.5 1.6 0.2 Total $ 92.8 $ 92.9 $ 96.8

Income Taxes - Components of In

Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Document Fiscal Year Focus	2021
Current:
U.S. Federal	$ 0.4	$ 0.7	$ 0.7
State and local	0.3	0.2	0.2
Foreign	14.8	10.3	15.9
Total current tax expense	15.5	11.2	16.8
Deferred:
U.S. Federal	(57.1)	(0.4)	0.1
State and local	(2.6)	0.2	(0.1)
Foreign	(1.4)	(2.6)	(0.2)
Total deferred tax benefit	(61.1)	(2.8)	(0.2)
Total income tax (benefit) expense	$ (45.6)	$ 8.4	$ 16.6

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Holiday [Line Items]
Document Fiscal Year Focus	2021
Effective Income Tax Rate Reconciliation [Abstract]
U.S. Federal income tax rate	21.00%	21.00%	21.00%
State and local taxes, net of Federal income tax benefit	0.30%	4.20%	0.20%
Foreign operations tax effect	3.30%	17.30%	5.00%
Research and experimentation tax credits	(3.80%)	(29.50%)	(5.00%)
Valuation allowance	(57.10%)	85.40%	15.00%
Tax contingencies	0.60%	0.30%	1.30%
Tax holiday	(10.10%)	(37.80%)	(24.60%)
Foreign taxes	1.00%	2.80%	2.10%
Other, principally non-tax deductible items	(0.20%)	1.00%	(2.90%)
Stock-based compensation	4.80%	11.30%	3.00%
Other, principally non-tax deductible items	0.10%	1.10%	0.30%
Prior period items	(0.50%)	(8.80%)	(1.00%)
Effective income tax rate	(43.60%)	74.30%	25.00%
Foreign statutory income tax rate	(2.30%)	12.10%	10.60%
Effective Income Tax Rate Reconciliation, Foreign Currency Adjustments, Percent	(0.70%)	(6.10%)	0.00%
Foreign Tax Authority
Effective Income Tax Rate Reconciliation [Abstract]
Tax holiday	(7.20%)
Effective income tax rate reconciliation, tax holiday	$ 10.7	$ 3.8	$ 14.6
Income tax holiday benefit (usd per share)	$ 0.12	$ 0.04	$ 0.16
Inland Revenue, Singapore (IRAS) | Foreign Tax Authority
Effective Income Tax Rate Reconciliation [Abstract]
Foreign statutory income tax rate	24.00%

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Valuation Allowance [Line Items]
Document Fiscal Year Focus	2021
Deferred tax assets, valuation allowance, judgment regarding the realizability of the beginning of the year deferred tax asset	$ 39.1
Deferred Income Taxes and Other Assets, Noncurrent	78.7	$ 19.9
Deferred Tax Assets, Goodwill and Intangible Assets	0.6	0
Deferred Tax Assets, Undistributed Foreign Earnings	1.6	0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	59.1
Deferred tax assets:
Accrued compensation, principally post-retirement, and other employee benefits	10.4	14.1
Accrued expenses, principally for state income taxes and warranty	6.1	8.6
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities	5.9	7.7
Net operating loss and other carryforwards	70.9	71.6
Inventories, principally due to reserves for financial reporting purposes and capitalization for tax purposes	7.7	6.5
Convertible note hedges	0	1.8
Plant and equipment, principally due to differences in depreciation	17	13
Total gross deferred tax assets	120.2	123.3
Valuation allowance	(39.1)	(98)	$ (85.3)
Total deferred tax assets	81.1	25.3
Deferred tax liabilities:
Intangible assets, principally due to different tax and financial reporting bases	0	(4.3)
Debt discount on convertible notes	0	(1.4)
Deferred Tax Liabilities, Undistributed Foreign Earnings	0	(0.9)
Other liabilities	(3)	(0.8)
Total gross deferred tax liabilities	(3)	(7.4)
Classified as follows in the Consolidated Balance Sheets:
Net deferred tax asset	78.1	17.9
Deferred Income Tax Liabilities, Net	$ (0.6)	$ (2)

Income Taxes - Net Operating Lo

Income Taxes - Net Operating Loss and Tax Credit Carryforwards (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Document Fiscal Year Focus	2021
Effective Income Tax Rate Reconciliation, Tax Holiday, Percent	10.10%	37.80%	24.60%
Valuation Allowance [Abstract]
Deferred tax assets, valuation allowance, judgment regarding the realizability of the beginning of the year deferred tax asset	$ 39.1
Income Tax Credits [Abstract]
Undistributed earnings of foreign subsidiaries	1,100
State and Local Jurisdiction
Net Operating Loss Carryforwards [Abstract]
Operating loss carryforwards, subject to expiration	49.5
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Income Tax Holiday, Aggregate Dollar Amount	$ 10.7	$ 3.8	$ 14.6
Effective Income Tax Rate Reconciliation, Tax Holiday, Percent	7.20%
Net Operating Loss Carryforwards [Abstract]
Operating loss carryforwards	$ 14.3
Operating Loss Carryforwards, Subject to Expiration in 5-10 years	1.4
Operating Loss Carryforwards, Subject to Expiration in 10-20 years	9.4
Operating Loss Carryforwards, Not Subject to Expiration	$ 2.8
Income Tax Credits [Abstract]
Income Tax Holiday, Income Tax Benefits Per Share	$ 0.12	$ 0.04	$ 0.16
Operating Loss Carryforwards, Subject to Expiration in up to 5 years	$ 0.1
Domestic Tax Authority
Net Operating Loss Carryforwards [Abstract]
Operating loss carryforwards	20.6
Operating Loss Carryforwards, Subject to Expiration in 5-10 years	7.3
Operating Loss Carryforwards, Subject to Expiration in 10-20 years	13.3
Research Tax Credit Carryforward
Income Tax Credits [Abstract]
Tax credit carryforward amount	26.8
Foreign Tax Credit Carryforward
Income Tax Credits [Abstract]
Tax credit carryforward amount	16.4
State Tax Credit Carryforward
Income Tax Credits [Abstract]
Tax credit carryforward amount	20.4
Tax Year 2022 Through Tax Year 2036 | State Tax Credit Carryforward
Income Tax Credits [Abstract]
Tax credit carryforward amount	2.9
After Tax Year 2036 | State Tax Credit Carryforward
Income Tax Credits [Abstract]
Tax credit carryforward amount	$ 17.5

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Interest expense on income taxes	$ 0	$ 0	$ 0
Potential penalty expense	0	0	0
Total accrued liabilities	0.3	0.3	0.3
Potential benefit on the effective tax rate	2
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits beginning balance	10.2	12.7	10.1
Settlements			(0.1)
Additions for tax positions of prior years			2.8
Reductions for tax positions of prior years	(0.3)
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	(0.4)	(2.6)
Unrecognized tax benefits ending balance	$ 9.5	$ 10.2	12.7
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions			$ 0.1

Equity Incentive Program - Shar

Equity Incentive Program - Share Based Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Document Fiscal Year Focus	2021
Pre-tax compensation expense	$ 32.1	$ 17.3	$ 25.2
Tax benefit	5.1	0	0
Total stock-based compensation expense, net of tax	27	17.3	25.2
Selling and Administrative Expenses
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Pre-tax compensation expense	25	9.4	16
Research and Development Expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Pre-tax compensation expense	5.5	6.2	7.7
Cost of Sales
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Pre-tax compensation expense	$ 1.6	$ 1.7	$ 1.5
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate	36.00%
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 2.5
Performance Shares [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 10
Maximum [Member] | Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate		40.60%	42.90%

Equity Incentive Program - Stoc

Equity Incentive Program - Stock Options and SSARs (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SSARs, Number of Shares (in shares):
Forfeited	0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk-free interest rate	0.06%
Dividend yield	0.00%	0.00%
Expected life (years)	4 years 6 months		4 years 6 months
Volatility	36.00%
SSARs, Weighted-average grant date fair value (in dollars per share):
Granted	$ 20.61
Stock Options, Number of Shares (in share):
Beginning balance	5,765,903
Granted	220,963
Exercised	(1,540,314)
Forfeited	(119,662)
Expired	(848,452)
Ending balance	3,478,438	5,765,903
Exercisable	2,645,456
Stock Options, Weighted Average Exercise Price (in dollars per share):
Beginning balance	$ 17.44
Granted	20.61
Exercised	16.64
Forfeited	17.35
Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price	29.52
Ending balance	15.04	$ 17.44
Exercisable	$ 14.25
SARS and Options, Additional Disclosures
Options, aggregate intrinsic value, outstanding	$ 28.9
Options, aggregate intrinsic value, exercisable	$ 24.1
Options, weighted average remaining contractual term, outstanding	3 years 1 month 6 days
Options, weighted average remaining contractual term, exercisable	2 years 4 months 24 days
Unrecognized compensation expense	$ 2.5
Weighted average period for compensation expense to be recognized	1 year 1 month 6 days
SSARs and Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Dividend yield			0.00%
SSARs
SSARs, Number of Shares (in shares):
Beginning balance	596,537
Granted	0
Exercised	(114,096)
Expired	(106,477)
Ending balance	375,964	596,537
Exercisable	375,964
SSARs, Weighted-average grant date fair value (in dollars per share):
Beginning balance	$ 22.72
Granted	0
Exercised	21.77
Forfeited	0
Expired	22.17
Ending balance	23.16	$ 22.72
Exercisable	23.16
Stock Options, Weighted Average Exercise Price (in dollars per share):
Granted	$ 0
SARS and Options, Additional Disclosures
SSARs, aggregate intrinsic value, outstanding	$ 0.2
SSARs, aggregate intrinsic value, exercisable	$ 0.2
SSARs, weighted average remaining contractual terms, outstanding	9 months 18 days
SSARs, weighted average remaining contractual term, exercisable	9 months 18 days
Unrecognized compensation expense	$ 0
Minimum | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk-free interest rate		0.11%	1.55%
Expected life (years)		4 years 3 months 18 days
Volatility		38.80%	40.00%
Fair value at date of grant	$ 6.14	$ 4.78	$ 6.22
Maximum | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk-free interest rate		1.42%	2.44%
Expected life (years)		4 years 6 months
Volatility		40.60%	42.90%
Fair value at date of grant	$ 6.31	$ 5.95	$ 7.45

Equity Incentive Program - RSUs

Equity Incentive Program - RSUs (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of SSARs that are exercisable | $	$ 21.9
Stock Options
Weighted Average Grant Date Fair Value (in dollars per share):
Unrecognized compensation expense | $	$ 2.5
Weighted average period for compensation expense to be recognized	1 year 1 month 6 days
Restricted Stock Units (RSUs)
Number of Shares (in shares):
Beginning balance | shares	1,909,786
Granted | shares	1,159,374
Vested (1) | shares	(1,068,104)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period | shares	(222,417)
Ending balance | shares	1,778,639
Weighted Average Grant Date Fair Value (in dollars per share):
Beginning balance | $ / shares	$ 16.14
Granted | $ / shares	20.59
Vested (1) | $ / shares	15.81
Forfeited | $ / shares	18.42
Ending balance | $ / shares	$ 18.89
Unrecognized compensation expense | $	$ 19.7
Weighted average period for compensation expense to be recognized	1 year 7 months 6 days

Equity Incentive Program - Addi

Equity Incentive Program - Additional Information (Details) shares in Millions	12 Months Ended
	Dec. 31, 2021shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	16.1
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	11
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period	7 years

Equity Incentive Program Equity

Equity Incentive Program Equity Incentive Program - Other Information Regarding SSARs and Stock Options (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Document Fiscal Year Focus	2021
Fair value of SSARs that are exercisable	$ 21.9
Cash received by Knowles for exercise of stock options	25.6	$ 1.8	$ 9.8
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	1.2	0	0
SSARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of SSARs exercised	0.1	0	0.4
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received by Knowles for exercise of stock options	25.6	1.8	9.8
Aggregate intrinsic value of stock options exercised	$ 6.6	$ 0.4	$ 2.7

Equity Incentive Program Equi_2

Equity Incentive Program Equity Incentive Program - PSUs (Details) - Performance Shares [Member] $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2021USD ($)	Mar. 31, 2021numberOfGrantees	Dec. 31, 2021USD ($)$ / sharesshares	Dec. 31, 2020$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | shares			766,466	920,973
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares			293,874
Vested (1) | shares			(346,898)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period | shares			(101,483)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value | $ / shares			$ 21.28	$ 16.04
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value | $ / shares			28.49
Vested (1) | $ / shares			14.13
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value | $ / shares			$ 19.05
Unrecognized compensation expense | $			$ 10
Weighted average period for compensation expense to be recognized			1 year 2 months 12 days
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Incremental Increase of Initial Grant Value, Percentage			0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Incremental Increase of Initial Grant Value, Percentage			225.00%
2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Plan Modification, Number of Grantees Affected	3.9	9
2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Plan Modification, Number of Grantees Affected	2.4	8
2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Plan Modification, Number of Grantees Affected	4.7	8

Employee Benefit Plans - Additi

Employee Benefit Plans - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)pension_plan	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan expense	$ 6.2	$ 6.2	$ 7.2
Document Fiscal Year Focus	2021
Number of defined benefit pension plans | pension_plan	4
Actuarial losses arising during period, net of tax	$ (4.3)	4	3.7
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Amortization of recognized actuarial loss	$ 0.8	$ 0.5	$ 0.4

Employee Benefit Plans - Change

Employee Benefit Plans - Change in Benefit Obligation and Funded Status (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Document Fiscal Year Focus	2021
Foreign Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	$ 74.5	$ 64.1
Service cost	0.3	0.3	$ 0.3
Interest cost	0.9	1.2	1.5
Defined Benefit Plan, Benefit Obligation, Benefits Paid	1.6	1.7
Actuarial (gain) loss (1)	(3.8)	(8.3)
Currency translation and other	(0.8)	2.5
Benefit obligation at end of year	69.5	74.5	64.1
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	65.7	58.2
Actual return on plan assets	4.6	5.8
Company contributions	1.5	1.5
Defined Benefit Plan, Plan Assets, Benefits Paid	1.6	1.7
Defined Benefit Plan, Plan Assets, Payment for Settlement	0	0.2
Currency translation and other	(0.9)	2.1
Fair value of plan assets at end of year	69.3	65.7	$ 58.2
Funded status	(0.2)	(8.8)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]
Other assets and deferred charges	2.6	0
Other liabilities	(2.8)	(8.8)
Funded status	(0.2)	(8.8)
Accumulated Other Comprehensive Loss (Earnings) [Abstract]
Net actuarial losses	19.2	25.6
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	1.1	1.1
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), Tax	(3.3)	(4.8)
Total accumulated other comprehensive loss, net of tax	17	21.9
Accumulated benefit obligation	68.4	73.3
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	$ 0	$ (0.2)

Employee Benefit Plans - Accumu

Employee Benefit Plans - Accumulated Benefit Obligations in Excess of Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Document Fiscal Year Focus	2021
Foreign Plan [Member]
Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets [Abstract]
Projected benefit obligation	$ 42.6	$ 74.5
Accumulated benefit obligation	40	43
Fair value of plan assets	37.8	34.8
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	$ 39.9	$ 65.7

Employee Benefit Plans - Compon

Employee Benefit Plans - Components of the Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Document Fiscal Year Focus	2021
Components of Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	$ 0	$ 0.1	$ 0.1
Foreign Plan [Member]
Components of Net Periodic Benefit Cost [Abstract]
Service cost	0.3	0.3	0.3
Interest cost	0.9	1.2	1.5
Expected return on plan assets	(2.8)	(2.4)	(2.4)
Amortization of recognized actuarial loss	0.8	0.5	0.4
Defined Benefit Plan, Other Cost (Credit)	0	0	0.1
Total net periodic benefit cost (income)	$ (0.8)	$ (0.3)	$ 0

Employee Benefit Plans - Actuar

Employee Benefit Plans - Actuarial Assumptions (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Document Fiscal Year Focus	2021
UNITED KINGDOM
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	1.84%	1.28%
Average wage increase	4.65%	4.20%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	1.28%	2.00%	2.80%
Average wage increase	4.20%	4.25%	4.40%
Expected return on plan assets	4.34%	4.35%	4.82%
TAIWAN, PROVINCE OF CHINA
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	0.75%	0.25%
Average wage increase	4.00%	4.00%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	0.25%	0.75%	1.25%
Average wage increase	4.00%	4.00%	4.25%
Expected return on plan assets	3.50%	3.75%	2.00%
PHILIPPINES
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	5.25%	4.00%
Average wage increase	4.00%	4.00%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	4.00%	5.00%	8.25%
Average wage increase	4.00%	5.00%	6.00%
Foreign Plan [Member]
Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	1.83%	1.27%
Average wage increase	4.59%	4.18%
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount rate	1.27%	1.97%	2.78%
Average wage increase	4.18%	4.24%	4.41%
Expected return on plan assets	4.32%	4.33%	4.72%

Employee Benefit Plans - Fair V

Employee Benefit Plans - Fair Value of Plan Assets by Category (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
PHILIPPINES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	4.00%	4.00%
TAIWAN, PROVINCE OF CHINA
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	4.00%	4.00%
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	4.65%	4.20%
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	4.59%	4.18%
Fair value of plan assets	$ 69.3	$ 65.7	$ 58.2
Foreign Plan [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13	11.6
Foreign Plan [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	56.3	54.1
Foreign Plan [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Fixed income investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	29.6	28.3
Foreign Plan [Member] | Fixed income investments | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3.5	3.4
Foreign Plan [Member] | Fixed income investments | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	26.1	24.9
Foreign Plan [Member] | Fixed income investments | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Common stock funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18.9	18.9
Foreign Plan [Member] | Common stock funds | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Common stock funds | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18.9	18.9
Foreign Plan [Member] | Common stock funds | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5.5	5
Foreign Plan [Member] | Real Estate Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Real Estate Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5.5	5
Foreign Plan [Member] | Real Estate Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Cash and equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.5	0.3
Foreign Plan [Member] | Cash and equivalents | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.5	0.3
Foreign Plan [Member] | Cash and equivalents | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Cash and equivalents | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Foreign Plan [Member] | Other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14.8	13.2
Foreign Plan [Member] | Other | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9	7.9
Foreign Plan [Member] | Other | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5.8	5.3
Foreign Plan [Member] | Other | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

Employee Benefit Plans - Future

Employee Benefit Plans - Future Estimates (Details) - Foreign Plan [Member] $ in Millions	Dec. 31, 2021USD ($)
Expected Future Benefit Payments [Abstract]
2018	$ 2.1
2019	1.9
2020	2.1
2021	2.6
2022	2.6
2023 - 2027	14.3
Estimated Future Employer Contributions [Abstract]
Estimated 2018 employer contribution	$ 1.3

Employee Benefit Plans - Supple

Employee Benefit Plans - Supplemental Retirement Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax	$ 4.3	$ (4)	$ (3.7)
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax	$ 17	$ 21.9

Other Comprehensive (Loss) Ea_3

Other Comprehensive (Loss) Earnings - Amounts Recognized in OCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Foreign currency translation:
Foreign currency translation, before tax	$ (3.6)	$ 13.8	$ 1.3
Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Tax, Portion Attributable to Parent	0	0	0
Foreign currency translation, net of tax	(3.6)	13.8	1.3
Employee benefit plans:
Employee benefit plans, before Tax	6.6	(4.4)	(3.2)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax, Attributable to Parent	(1.6)	1	0
Net change in employee benefit plans	5	(3.4)	(3.2)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax	(1.6)	1.4	1.1
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(1.3)	0.7	(0.2)
Changes in fair value of cash flow hedges:
Change in fair value of cash flow hedges, tax	0.3	(0.3)	(0.2)
Total cash flow hedges	(1.3)	1.1	0.9
Total:
Other Comprehensive Income (Loss), before tax	1.4	10.8	(0.8)
Other comprehensive earnings (loss), net of tax	$ 0.1	$ 11.5	$ (1)

Other Comprehensive (Loss) Ea_4

Other Comprehensive (Loss) Earnings - Components of AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Components of AOCI [Abstract]
Beginning balance	$ (100.5)	$ (112)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0.1	11.5	$ (1)
Ending balance	(100.4)	(100.5)	(112)
Cash flow hedges
Components of AOCI [Abstract]
Beginning balance	1.6	0.5
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(1.3)	1.1
Ending balance	0.3	1.6	0.5
Employee benefit plans
Components of AOCI [Abstract]
Beginning balance	(22.1)	(18.7)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	5	(3.4)
Ending balance	(17.1)	(22.1)	(18.7)
Cumulative foreign currency translation adjustments
Components of AOCI [Abstract]
Beginning balance	(80)	(93.8)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(3.6)	13.8
Ending balance	$ (83.6)	$ (80)	$ (93.8)

Other Comprehensive (Loss) Ea_5

Other Comprehensive (Loss) Earnings - Changes in Components of AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Pension and Postretirement Benefit Plans [Abstract]
Amortization or settlement of actuarial losses and prior service costs	$ 0.9	$ 0.7	$ 0.6
Tax	(0.2)	(0.1)	(0.1)
Net of tax	0.7	0.6	0.5
Cash Flow Hedges [Abstract]
Net (gains) losses reclassified into earnings	(2.1)	(1.2)	0.9
Other Comprehensive Income (Loss) before Reclassifications, Tax		0.3
Tax	0.5		(0.2)
Net of tax	$ (1.6)	$ (0.9)	$ 0.7

Segment Information - Informati

Segment Information - Information on Reportable Segments (Details) $ in Millions		12 Months Ended
		Dec. 31, 2021USD ($)segments	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Segment Reporting Information [Line Items]
Document Fiscal Year Focus		2021
Number of reportable segments | segments		2
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenues		$ 868.1	$ 764.3	$ 854.8
Reconciliation of Net Earnings from Segments [Abstract]
Interest expense, net		14.2	16.4	14.5
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest	[1]	104.6	11.3	66.3
(Benefit from) provision for income taxes		(45.6)	8.4	16.6
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent		150.2	2.9	49.7
Reconciliation of Depreciation and Amortization [Abstract]
Depreciation and amortization		62.5	60.6	54.4
Reconciliation of Research and Development Expense [Abstract]
Research and development expenses		92.8	92.9	96.8
Operating segments
Reconciliation of Net Earnings from Segments [Abstract]
(Loss) earnings before interest and income taxes	[1]	180.7	76.6	137.7
Reconciliation of Capital Expenditures [Abstract]
Capital expenditures		48.6	31.9	41.2
Reconciliation of Research and Development Expense [Abstract]
Research and development expenses		92.8	92.9	96.8
Operating segments | Audio
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenues		667	591.2	682.8
Reconciliation of Net Earnings from Segments [Abstract]
(Loss) earnings before interest and income taxes		137	44.9	107.3
Reconciliation of Depreciation and Amortization [Abstract]
Depreciation and amortization		46.2	47	41.3
Reconciliation of Capital Expenditures [Abstract]
Capital expenditures		40.8	21.9	24
Reconciliation of Research and Development Expense [Abstract]
Research and development expenses		81.8	84.6	90.8
Operating segments | Precision Devices
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenues		201.1	173.1	172
Reconciliation of Net Earnings from Segments [Abstract]
(Loss) earnings before interest and income taxes		43.7	31.7	30.4
Reconciliation of Depreciation and Amortization [Abstract]
Depreciation and amortization		13.3	10.5	9.9
Reconciliation of Capital Expenditures [Abstract]
Capital expenditures		5.6	9.6	16.5
Reconciliation of Research and Development Expense [Abstract]
Research and development expenses		10.5	6.7	5.8
Corporate, Non-Segment [Member]
Reconciliation of Depreciation and Amortization [Abstract]
Depreciation and amortization		3	3.1	3.2
Reconciliation of Capital Expenditures [Abstract]
Capital expenditures		2.2	0.4	0.7
Reconciliation of Research and Development Expense [Abstract]
Research and development expenses		0.5	1.6	0.2
Corporate Expense and Other		$ 61.9	$ 48.9	$ 56.9
[1]	Years Ended December 31, (in millions) 2021 2020 2019 Revenues: Audio $ 667.0 $ 591.2 $ 682.8 Precision Devices 201.1 173.1 172.0 Total revenues $ 868.1 $ 764.3 $ 854.8 Earnings from continuing operations before interest and income taxes: Audio $ 137.0 $ 44.9 $ 107.3 Precision Devices 43.7 31.7 30.4 Total segments 180.7 76.6 137.7 Corporate expense / other 61.9 48.9 56.9 Interest expense, net 14.2 16.4 14.5 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations $ 150.2 $ 2.9 $ 49.7 Depreciation and amortization: Audio $ 46.2 $ 47.0 $ 41.3 Precision Devices 13.3 10.5 9.9 Corporate 3.0 3.1 3.2 Total $ 62.5 $ 60.6 $ 54.4 Capital expenditures: Audio $ 40.8 $ 21.9 $ 24.0 Precision Devices 5.6 9.6 16.5 Corporate 2.2 0.4 0.7 Total $ 48.6 $ 31.9 $ 41.2 Research and development: Audio $ 81.8 $ 84.6 $ 90.8 Precision Devices 10.5 6.7 5.8 Corporate 0.5 1.6 0.2 Total $ 92.8 $ 92.9 $ 96.8

Segment Information - Reportabl

Segment Information - Reportable Segments Adjusted Working Capital and Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Document Fiscal Year Focus	2021
Revenues	$ 868.1	$ 764.3	$ 854.8
Total assets	1,731.6	1,654.9
Operating segments | Audio
Segment Reporting Information [Line Items]
Revenues	667	591.2	682.8
Total assets	1,467.1	1,470.4
Operating segments | Precision Devices
Segment Reporting Information [Line Items]
Revenues	201.1	173.1	$ 172
Total assets	260.4	179.2
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Total assets	$ 4.1	$ 5.3

Segment Information - Revenue b

Segment Information - Revenue by Geographic Location (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Document Fiscal Year Focus	2021
Revenues	$ 868.1	$ 764.3	$ 854.8
Long-Lived Assets	218.2	214.8
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	611.5	559.6	614.7
Long-Lived Assets	149.5	140.5
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	153.2	116.7	130.4
Long-Lived Assets	64.6	69.8
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	93.5	80	97.4
Long-Lived Assets	3.1	3.3
Other Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	5.5	3.7	6.3
Long-Lived Assets	1	1.2
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	4.4	4.3	$ 6
Long-Lived Assets	$ 0	$ 0

Segment Information Segment Inf

Segment Information Segment Information - Concentration of Credit Risk (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Concentration Risk [Line Items]
Document Fiscal Year Focus	2021
Customer Concentration Risk [Member] | Revenue, Segment Benchmark [Member] | Customer A
Concentration Risk [Line Items]
Concentration Risk, Percentage	16.00%	23.00%	22.00%

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of information used in computing basic and diluted earnings per share [Abstract]
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent		$ 150.2	$ 2.9	$ 49.7
Earnings (loss) from discontinued operations, net		0.2	3.7	(0.6)
Net earnings		$ 150.4	$ 6.6	$ 49.1
Basic earnings (loss) per common share:
Income (Loss) from Continuing Operations, Per Basic Share		$ 1.63	$ 0.03	$ 0.55
Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share		0	0.04	(0.01)
Earnings Per Share, Basic		$ 1.63	$ 0.07	$ 0.54
Basic weighted average shares outstanding (in shares)	[1]	92,300,000	91,700,000	91,200,000
Diluted earnings (loss) per common share:
Income (Loss) from Continuing Operations, Per Diluted Share		$ 1.59	$ 0.03	$ 0.53
Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Diluted Share		0	0.04	0
Earnings Per Share, Diluted		$ 1.59	$ 0.07	$ 0.53
Dilutive weighted average shares outstanding (in shares)	[1]	94,700,000	92,900,000	93,400,000
Weighted average number of anti-dilutive shares excluded from the calculation (in shares)		700,000	3,900,000	2,800,000
[1]	Years Ended December 31, 2021 2020 2019 Revenues $ 868.1 $ 764.3 $ 854.8 Cost of goods sold 508.6 490.8 525.1 Restructuring charges - cost of goods sold — 2.3 1.7 Gross profit 359.5 271.2 328.0 Research and development expenses 92.8 92.9 96.8 Selling and administrative expenses 146.4 131.5 145.7 Impairment charges 4.0 7.6 — Restructuring charges 0.5 10.0 4.3 Operating expenses 243.7 242.0 246.8 Operating earnings 115.8 29.2 81.2 Interest expense, net 14.2 16.4 14.5 Other (income) expense, net (3.0) 1.5 0.4 Earnings before income taxes and discontinued operations 104.6 11.3 66.3 (Benefit from) provision for income taxes (45.6) 8.4 16.6 Earnings from continuing operations 150.2 2.9 49.7 Earnings (loss) from discontinued operations, net 0.2 3.7 (0.6) Net earnings $ 150.4 $ 6.6 $ 49.1 Earnings per share from continuing operations: Basic $ 1.63 $ 0.03 $ 0.55 Diluted $ 1.59 $ 0.03 $ 0.53 Earnings (loss) per share from discontinued operations: Basic $ — $ 0.04 $ (0.01) Diluted $ — $ 0.04 $ — Net earnings per share: Basic $ 1.63 $ 0.07 $ 0.54 Diluted $ 1.59 $ 0.07 $ 0.53 Weighted-average common shares outstanding: Basic 92.3 91.7 91.2 Diluted 94.7 92.9 93.4

Schedule II - Valuation and Q_2

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Document Fiscal Year Focus	2021
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Valuation allowance	$ 39.1	$ 98	$ 85.3
Allowance for doubtful accounts receivable	0.2	1.6	0.8
Allowance for Doubtful Accounts
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Period Increase (Decrease)	(0.2)
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	1.6	0.8	0.6
Charged to Cost and Expense		0.8	0.3
Accounts Written off / Reductions	(1.2)	0	(0.1)
Balance at End of Year		1.6	0.8
Deferred Tax Valuation Allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	98	85.3	131.2
Additions	0	12.7	0
Accounts Written off / Reductions	$ (58.9)	0	(45.9)
Balance at End of Year		$ 98	$ 85.3

Uncategorized Items - kn-202112

Label	Element	Value
Cash and Cash Equivalents, at Carrying Value, Including Discontinued Operations	us-gaap_CashAndCashEquivalentsAtCarryingValueIncludingDiscontinuedOperations	$ 73,500,000