| Cover Page Document | Feb. 04, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Feb. 4, 2021 |
| Entity Registrant Name | PIPER SANDLER COMPANIES |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 1-31720 |
| Entity Tax Identification Number | 30-0168701 |
| Entity Address, Address Line One | 800 Nicollet Mall, Suite 900 |
| Entity Address, City or Town | Minneapolis |
| Entity Address, State or Province | MN |
| Entity Address, Postal Zip Code | 55402 |
| City Area Code | (612) |
| Local Phone Number | 303-6000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.01 per share |
| Trading Symbol | PIPR |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001230245 |
| Amendment Flag | false |
