Basis of Financial Statement Presentation (Policies)	3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying Condensed Consolidated Financial Statements include the accounts of Lydall, Inc. and its subsidiaries. All financial information is unaudited for the interim periods reported. All significant intercompany transactions have been eliminated in the Condensed Consolidated Financial Statements. The Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The year-end Condensed Consolidated Balance Sheet was derived from the audited financial statements for the year ended December 31, 2019, but does not include all disclosures required by U.S. GAAP. Management believes that all adjustments, which include only normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position, results of operations and cash flows for the periods reported, have been included. For further information, refer to the audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. The full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, including sales, expenses, reserves and allowances, manufacturing, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19. The Company has made estimates of the impact of COVID-19 within its financial statements and there may be changes to those estimates in future periods. Actual results could differ from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Effective January 1, 2020, the Company adopted the Financial Accounting Standards Board ("FASB") Accounting Standards Update ("ASU") 2016-13, "Financial Instruments - Credit Losses (Topic 326)." The new standard amends guidance on reporting credit losses for assets held at amortized cost basis. The Company has determined the only financial assets subject to the new standard are its trade receivables and contract assets. The adoption of this ASU did not have any impact on the Company’s consolidated financial statements and disclosures. Effective January 1, 2020, the Company adopted the FASB issued ASU 2018-13, "Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement," which adds, amends and removes certain disclosure requirements related to fair value measurements. Among other changes, this standard requires certain additional disclosure surrounding Level 3 assets, including changes in unrealized gains or losses in other comprehensive income and certain inputs in those measurements. Please refer to Note 5, “Impairments of Goodwill and Other Long-Lived Assets”, for discussion of level 3 unobservable inputs used in the quantitative impairment assessments for the quarter ended March 31, 2020. Effective January 1, 2020, the Company adopted FASB issued ASU 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40); Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract." The amendments in this update require implementation costs incurred by customers in cloud computing arrangements (i.e., hosting arrangements) to be capitalized under the same premises of authoritative guidance for internal-use software, and deferred over the noncancellable term of the cloud computing arrangement plus any option renewal periods that are reasonably certain to be exercised by the customer or for which the exercise is controlled by the service provider. The adoption of this ASU did not have any impact on the Company’s consolidated financial statements and disclosures. In March 2020, the FASB issued ASU 2020-04, "Reference Rate Reform (Topic 848); Facilitation of the Effects of Reference Rate Reform on Financial Reporting." The amendments in this update are elective, and provide optional expedients and exceptions in accounting for contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. The guidance in this update is effective for transactions entered into between March 12, 2020 and December 31, 2022. The Company adopted this ASU upon issuance and notes no impact to the Company's consolidated financial statements and disclosures as of March 31, 2020. In January 2020, the FASB issued ASU 2020-01, "Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)." The amendments in this update are intended to reduce diversity in practice and increase comparability of the accounting for interaction of equity securities, investments accounted for under the equity method of accounting, and the accounting for certain forward contracts and purchased options accounted for under Topic 815. This ASU is effective for fiscal years and interim periods beginning after December 15, 2020 with early adoption permitted. The Company is currently evaluating the impact of this update on its consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes". The new standard is intended to simplify accounting for income taxes by removing certain exceptions to the general principles in Topic 740, and by clarifying and amending existing guidance in other areas of the same topic. This ASU is effective for fiscal years and interim periods beginning after December 15, 2020 with early adoption permitted. The Company is currently evaluating the impact of this update on its consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU No. 2018-14, "Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans." This ASU requires entities to disclose the weighted-average interest crediting rates for cash balance plans and other plans with promised interest crediting rates. This ASU also requires entities to disclose an explanation for significant gains and losses related to changes in the benefit obligation for the period. This ASU is effective for fiscal years beginning after December 15, 2020 with early adoption permitted. The Company is currently evaluating the method and impact the adoption of this ASU will have on its consolidated financial statements and disclosures.
Risks and uncertainties	Risks and uncertainties Worldwide economic cycles, political changes and the COVID-19 pandemic affect the markets that the Company’s businesses serve and affect demand for the Company's products and could impact profitability. Among other factors, disruptions in the global credit and financial markets, including diminished liquidity and credit availability, changes in international trade agreements, swings in consumer confidence and spending, unstable economic growth and fluctuations in unemployment rates has caused economic instability and can have a negative impact on the Company’s results of operations, financial condition and liquidity.
Derivatives	Derivatives The Company selectively uses financial instruments to manage market risk associated with exposure to fluctuations in interest rates and foreign currency rates. These financial exposures are monitored and managed by the Company as an integral part of its risk management program. Interest Rate Hedging The Company’s interest rate exposure is most sensitive to fluctuations in interest rates in the United States and Europe, which impact interest paid on its debt. The Company has debt with variable rates of interest based generally on LIBOR. From time to time, the Company enters into interest rate swap agreements to manage interest rate risk. These instruments are designated as cash flow hedges and are recorded at fair value using Level 2 observable market inputs.

Basis of Financial Statement Presentation (Policies)

3 Months Ended

Mar. 31, 2020

The accompanying Condensed Consolidated Financial Statements include the accounts of Lydall, Inc. and its subsidiaries. All financial information is unaudited for the interim periods reported. All significant intercompany transactions have been eliminated in the Condensed Consolidated Financial Statements. The Condensed Consolidated Financial Statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). The year-end Condensed Consolidated Balance Sheet was derived from the audited financial statements for the year ended December 31, 2019, but does not include all disclosures required by U.S. GAAP. Management believes that all adjustments, which include only normal recurring adjustments necessary for a fair statement of the Company’s condensed consolidated financial position, results of operations and cash flows for the periods reported, have been included. For further information, refer to the audited consolidated financial statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. The full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, including sales, expenses, reserves and allowances, manufacturing, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19. The Company has made estimates of the impact of COVID-19 within its financial statements and there may be changes to those estimates in future periods. Actual results could differ from those estimates.

Recent Accounting Pronouncements

Effective January 1, 2020, the Company adopted the Financial Accounting Standards Board ("FASB") Accounting Standards Update ("ASU") 2016-13, "Financial Instruments - Credit Losses (Topic 326)." The new standard amends guidance on reporting credit losses for assets held at amortized cost basis. The Company has determined the only financial assets subject to the new

standard are its trade receivables and contract assets. The adoption of this ASU did not have any impact on the Company’s consolidated financial statements and disclosures.

Effective January 1, 2020, the Company adopted the FASB issued ASU 2018-13, "Fair Value Measurement (Topic 820): Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement," which adds, amends and removes certain disclosure requirements related to fair value measurements. Among other changes, this standard requires certain additional disclosure surrounding Level 3 assets, including changes in unrealized gains or losses in other comprehensive income and certain inputs in those measurements. Please refer to Note 5, “Impairments of Goodwill and Other Long-Lived Assets”, for discussion of level 3 unobservable inputs used in the quantitative impairment assessments for the quarter ended March 31, 2020.

Effective January 1, 2020, the Company adopted FASB issued ASU 2018-15, "Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40); Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract." The amendments in this update require implementation costs incurred by customers in cloud computing arrangements (i.e., hosting arrangements) to be capitalized under the same premises of authoritative guidance for internal-use software, and deferred over the noncancellable term of the cloud computing arrangement plus any option renewal periods that are reasonably certain to be exercised by the customer or for which the exercise is controlled by the service provider. The adoption of this ASU did not have any impact on the Company’s consolidated financial statements and disclosures.

In March 2020, the FASB issued ASU 2020-04, "Reference Rate Reform (Topic 848); Facilitation of the Effects of Reference Rate Reform on Financial Reporting." The amendments in this update are elective, and provide optional expedients and exceptions in accounting for contracts, hedging relationships, and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. The guidance in this update is effective for transactions entered into between March 12, 2020 and December 31, 2022. The Company adopted this ASU upon issuance and notes no impact to the Company's consolidated financial statements and disclosures as of March 31, 2020.

In January 2020, the FASB issued ASU 2020-01, "Investments—Equity Securities (Topic 321), Investments—Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)." The amendments in this update are intended to reduce diversity in practice and increase comparability of the accounting for interaction of equity securities, investments accounted for under the equity method of accounting, and the accounting for certain forward contracts and purchased options accounted for under Topic 815. This ASU is effective for fiscal years and interim periods beginning after December 15, 2020 with early adoption permitted. The Company is currently evaluating the impact of this update on its consolidated financial statements and related disclosures.

In December 2019, the FASB issued ASU 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes". The new standard is intended to simplify accounting for income taxes by removing certain exceptions to the general principles in Topic 740, and by clarifying and amending existing guidance in other areas of the same topic. This ASU is effective for fiscal years and interim periods beginning after December 15, 2020 with early adoption permitted. The Company is currently evaluating the impact of this update on its consolidated financial statements and related disclosures.

In August 2018, the FASB issued ASU No. 2018-14, "Compensation - Retirement Benefits - Defined Benefit Plans - General (Subtopic 715-20): Disclosure Framework - Changes to the Disclosure Requirements for Defined Benefit Plans." This ASU requires entities to disclose the weighted-average interest crediting rates for cash balance plans and other plans with promised interest crediting rates. This ASU also requires entities to disclose an explanation for significant gains and losses related to changes in the benefit obligation for the period. This ASU is effective for fiscal years beginning after December 15, 2020 with early adoption permitted. The Company is currently evaluating the method and impact the adoption of this ASU will have on its consolidated financial statements and disclosures.

Risks and uncertainties

Worldwide economic cycles, political changes and the COVID-19 pandemic affect the markets that the Company’s businesses serve and affect demand for the Company's products and could impact profitability. Among other factors, disruptions in the global credit and financial markets, including diminished liquidity and credit availability, changes in international trade agreements, swings in consumer confidence and spending, unstable economic growth and fluctuations in unemployment rates has caused economic instability and can have a negative impact on the Company’s results of operations, financial condition and liquidity.

Derivatives

The Company selectively uses financial instruments to manage market risk associated with exposure to fluctuations in interest rates and foreign currency rates. These financial exposures are monitored and managed by the Company as an integral part of its risk management program.

Interest Rate Hedging

The Company’s interest rate exposure is most sensitive to fluctuations in interest rates in the United States and Europe, which impact interest paid on its debt. The Company has debt with variable rates of interest based generally on LIBOR. From time to time, the Company enters into interest rate swap agreements to manage interest rate risk. These instruments are designated as cash flow hedges and are recorded at fair value using Level 2 observable market inputs.