Acquisitions, Goodwill And Other Intangible Assets (Narrative) (Details) - CWDS, LLC - USD ($) $ in Millions	1 Months Ended
May 31, 2024	May 03, 2024
Acquired Intangible Assets
Purchase price	$ 20.0
Holdback payment	$ 1.0
Goodwill		$ 1.7
Identifiable intangible assets		$ 4.3

Business Combination, Holdback Payment

No definition available.

Name:	lcii_BusinessCombinationHoldbackPayment
Namespace Prefix:	lcii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

[Line Items] for Schedule of Acquired Intangible Assets [Table]

+ References

No definition available.

+ Details

Name:	lcii_ScheduleofAcquiredIntangibleAssetsLineItems
Namespace Prefix:	lcii_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-1

+ Details

Name:	us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 30
-Paragraph 8
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479637/805-30-30-8

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479581/805-30-50-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 30
-Paragraph 7
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479637/805-30-30-7

+ Details

Name:	us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-1

+ Details

Name:	us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_BusinessAcquisitionAxis=lcii_CWDSLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: