| Cover | Aug. 11, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Aug. 11, 2020 |
| Entity Registrant Name | LCI INDUSTRIES |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-13646 |
| Entity Tax Identification Number | 13-3250533 |
| Entity Address, Address Line One | 3501 County Road 6 East, |
| Entity Address, City or Town | Elkhart, |
| Entity Address, State or Province | IN |
| Entity Address, Postal Zip Code | 46514 |
| City Area Code | (574) |
| Local Phone Number | 535-1125 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Title of 12(b) Security | Common Stock, $.01 par value |
| Trading Symbol | LCII |
| Security Exchange Name | NYSE |
| Entity Central Index Key | 0000763744 |
| Amendment Flag | false |
