| Cover | Feb. 23, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Feb. 23, 2021 |
| Entity Registrant Name | Goosehead Insurance, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-38466 |
| Entity Tax Identification Number | 82-3886022 |
| Entity Address, Address Line One | 1500 Solana Boulevard |
| Entity Address, Address Line Two | Ste. 4500 |
| Entity Address, City or Town | Westlake |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 76262 |
| City Area Code | 214 |
| Local Phone Number | 838-5500 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Class A Common Stock, par value $.01 per share |
| Trading Symbol | GSHD |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Ex Transition Period | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001726978 |
