Environmental Loss Contingencies, Indemnification Asset

No definition available.

Name:	ldl_EnvironmentalLossContingenciesIndemnificationAsset
Namespace Prefix:	ldl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Site Contingency, Environmental Remediation Indemnity Secured In Environmental Escrow, Amount

+ References

No definition available.

+ Details

Name:	ldl_SiteContingencyEnvironmentalRemediationIndemnitySecuredInEnvironmentalEscrowAmount
Namespace Prefix:	ldl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Site Contingency, Environmental Remediation Indemnity Secured In General Indemnity Escrow, Amount

+ References

No definition available.

+ Details

Name:	ldl_SiteContingencyEnvironmentalRemediationIndemnitySecuredInGeneralIndemnityEscrowAmount
Namespace Prefix:	ldl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

Name:	us-gaap_LeaseAndRentalExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 10
-Subparagraph (c),(d)(2)
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859

+ Details

Name:	us-gaap_SiteContingencyLossExposureNotAccruedBestEstimate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_EnvironmentalRemediationSiteAxis=ldl_QuebecCanadaSiteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LitigationCaseAxis=ldl_GermanFederalCartelOfficeBundeskartellamtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=ldl_LydallGerhardiMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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Commitments and Contingencies (Additional Information) (Detail) € in Millions, CAD in Millions, $ in Millions		1 Months Ended		12 Months Ended
	Jul. 06, 2016 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 EUR (€)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2016 CAD
Loss Contingencies [Line Items]
Operating leases rent expense				$ 5.4	$ 5.1	$ 6.4
Quebec, Canada
Loss Contingencies [Line Items]
Environmental liability		$ 0.9		0.9
Environmental remediation indemnity secured by environmental escrow account		2.2		2.2			CAD 3.0
Environmental remediation indemnity secured by general indemnity escrow account		10.4		10.4			CAD 14.0
Indemnification asset, amount at acquisition date		0.9		$ 0.9
German Federal Cartel Office, Bundeskartellamt \| Lydall Gerhardi
Loss Contingencies [Line Items]
Litigation settlement amount awarded to (against) the entity		(3.5)	€ (3.3)
Litigation settlement expense		$ 3.5	€ 3.3
Minimum \| Quebec, Canada
Loss Contingencies [Line Items]
Estimated cost of remediation project	$ 0.9
Maximum \| Quebec, Canada
Loss Contingencies [Line Items]
Estimated cost of remediation project	$ 1.5