Payments to Acquire Businesses, Net of Cash Acquired, Including Additional Amount Paid

No definition available.

Name:	lcii_PaymentsToAcquireBusinessesNetOfCashAcquiredIncludingAdditionalAmountPaid
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

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

- 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

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-Name Accounting Standards Codification
-Section 30
-Paragraph 8
-SubTopic 30
-Topic 805
-Publisher FASB
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-Section 30
-Paragraph 7
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479637/805-30-30-7

+ Details

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

- Definition

Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479581/805-30-50-1

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-Topic 805
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-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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- Details

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Acquisitions, Goodwill And Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended
	Apr. 30, 2025	Mar. 31, 2025	Jun. 30, 2025
Freedman Seating Company
Acquired Intangible Assets
Cash consideration	$ 68,608
Debt assumed	10,000
Purchase price	$ 78,608
Freedman Seating Company \| Customer relationships
Acquired Intangible Assets
Estimated Useful Life in Years			10 years
Trans/Air Manufacturing Corporation
Acquired Intangible Assets
Cash consideration		$ 29,600
Maximum contingent consideration		$ 2,000