Debt Instrument, Additional Margin Interest Rate

No definition available.

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Period Type:	duration

- Definition

Letter Of Credit

+ References

No definition available.

+ Details

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Namespace Prefix:	lcii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit, Percentage Of Equity Interests Used As Security

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period After Request Is Issued For Interest Payable Rate To Be Determined

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, 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_DebtInstrumentTerm
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Data Type:	xbrli:durationItemType
Balance Type:	na
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

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Details

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- Details

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Balance Type:
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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LineOfCreditMember
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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Long-Term Indebtedness (Narrative) (Details) - USD ($)						3 Months Ended
Long-Term Indebtedness (Narrative) (Details) - USD ($)	Mar. 29, 2019	Dec. 14, 2018	Apr. 27, 2016	Mar. 20, 2015	Feb. 24, 2014	Mar. 31, 2019	Dec. 31, 2018
Line of Credit Facility
Long-term indebtedness						$ 286,311,000	$ 293,528,000
Remaining availability under the facilities						$ 514,400,000
Percentage of equity interests used as security						65.00%
Amended Credit Agreement
Line of Credit Facility
Maximum borrowings under line of credit		$ 300,000,000.0
JPMorgan Chase Bank And Wells Fargo Bank \| Line of Credit
Line of Credit Facility
Maximum borrowings under line of credit			$ 325,000,000.0
Letter Of Credit						$ 2,600,000
Remaining availability under the facilities						$ 364,400,000
JPMorgan Chase Bank And Wells Fargo Bank \| Line of Credit \| Prime Rate
Line of Credit Facility
Basis spread on variable rate						1.00%
JPMorgan Chase Bank And Wells Fargo Bank \| Line of Credit \| Prime Rate \| Minimum
Line of Credit Facility
Basis spread on variable rate						0.875%
Prudential Investment Management Inc \| Line of Credit
Line of Credit Facility
Long-term indebtedness		250,000,000.0		$ 50,000,000.0
Remaining availability under the facilities					$ 150,000,000.0
Debt term	3 years			5 years
Interest rate during period	3.80%			3.35%
Period after request is issued, by company, for interest payable rate to be determined by Prudential					5 days
JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank \| Line of Credit
Line of Credit Facility
Maximum borrowings under line of credit		$ 600,000,000.0
Option One \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank \| Line of Credit \| LIBOR \| Minimum
Line of Credit Facility
Debt instrument, additional margin interest rate			0.00%			0.00%
Option One \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank \| Line of Credit \| LIBOR \| Maximum
Line of Credit Facility
Debt instrument, additional margin interest rate		0.625%
Option One \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank \| Line of Credit \| Federal Funds Effective Rate
Line of Credit Facility
Basis spread on variable rate		0.50%
Option Two \| JPMorgan Chase Bank, N.A., Wells Fargo Bank, N.A., Bank of America, N.A., and 1st Source Bank \| Line of Credit \| LIBOR \| Maximum
Line of Credit Facility
Basis spread on variable rate		1.625%