Debt Instrument, Additional Margin Interest Rate

No definition available.

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- Definition

Letter Of Credit

+ References

No definition available.

+ Details

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

- Definition

Line of Credit Facility, Additional Maximum Borrowing Capacity Upon Approval

+ References

No definition available.

+ Details

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

- 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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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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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

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Balance Type:	na
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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Period Type:	instant

- 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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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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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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Balance Type:	credit
Period Type:	instant

- 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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- Details

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- Details

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Long-Term Indebtedness (Narrative) (Details) - USD ($)			12 Months Ended
Long-Term Indebtedness (Narrative) (Details) - USD ($)	Apr. 27, 2016	Mar. 20, 2015	Dec. 31, 2018	Dec. 14, 2018	Dec. 31, 2017	Mar. 30, 2017	Feb. 24, 2014
Line of Credit Facility
Long-term indebtedness			$ 293,528,000		$ 49,924,000
Maximum
Line of Credit Facility
Ownership percentage			65.00%
Line of Credit
Line of Credit Facility
Remaining availability under the facilities			$ 507,700,000
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			2,200,000		$ 2,400,000
Remaining availability under the facilities			$ 357,700,000
JPMorgan Chase Bank And Wells Fargo Bank \| Line of Credit \| Prime Rate
Line of Credit Facility
Interest rate			1.00%
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
Additional maximum borrowing capacity upon approval				300,000,000.0
Prudential Investment Management Inc \| Line of Credit
Line of Credit Facility
Long-term indebtedness		$ 50,000,000.0		$ 250,000,000.0
Remaining availability under the facilities						$ 150,000,000.0	$ 150,000,000.0
Weighted average interest rate		3.35%
Debt instrument term (in years)		5 years
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 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 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
Interest 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 \| Minimum
Line of Credit Facility
Interest rate			0.875%
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
Interest rate			1.625%