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.

No definition available.

+ Details

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

- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

Name:	us-gaap_DefinedBenefitPlanTargetPlanAssetAllocations
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

Name:	us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis=us-gaap_UnitedStatesPensionPlansOfUSEntityDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ldl_DomesticEquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=ldl_InternationalEquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_FixedIncomeSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_HedgeFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_RealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_CashAndCashEquivalentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Employer Sponsored Benefit Plan (Target Allocation and the Actual Allocation of Plan Assets) (Detail) - Domestic Pension Plan	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation of Plan Assets	30.00%	42.00%
International equities
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation of Plan Assets	30.00%	27.00%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation of Plan Assets	28.00%	28.00%
Hedge fund of funds
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation of Plan Assets	10.00%	0.00%
Real estate investment trusts
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Actual Allocation of Plan Assets	0.00%	0.00%
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Actual Allocation of Plan Assets	2.00%	3.00%
Minimum \| Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	25.00%
Minimum \| International equities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	25.00%
Minimum \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	25.00%
Minimum \| Hedge fund of funds
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	5.00%
Minimum \| Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	0.00%
Maximum \| Domestic equities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	35.00%
Maximum \| International equities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	35.00%
Maximum \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	35.00%
Maximum \| Hedge fund of funds
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	15.00%
Maximum \| Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation	5.00%