Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2021	Feb. 18, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Entity File Number	001-31720
Entity Registrant Name	PIPER SANDLER COMPANIES
Entity Incorporation, State or Country Code	DE
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
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	PIPR
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Common Stock, shares outstanding held by non-affiliates			17,485,346
Entity Public Float			$ 2.3
Entity Common Stock, shares outstanding		18,183,948
Entity Central Index Key	0001230245
Amendment Flag	false
Document Transition Report	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Auditor Name	Ernst & Young LLP
Auditor Location	Minneapolis, Minnesota
Auditor Firm ID	42