| Document Type Document | May 06, 2020 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | May 6, 2020 |
| Entity Registrant Name | Toll Brothers, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-09186 |
| Entity Tax Identification Number | 23-2416878 |
| Entity Address, Address Line One | 250 Gibraltar Road |
| Entity Address, City or Town | Horsham |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19044 |
| City Area Code | 215 |
| Local Phone Number | 938-8000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000794170 |
| Amendment Flag | false |
| Common Stock [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Common stock, par value $0.01 per share |
| Trading Symbol | TOL |
| Security Exchange Name | NYSE |
| Senior Notes Due 2024 [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Guarantee of Toll Brothers Finance Corp. 5.625% Senior Notes due 2024 |
| Trading Symbol | TOL/24 |
| Security Exchange Name | NYSE |
