Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Oct. 26, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-33554
Entity Registrant Name	PROS HOLDINGS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	76-0168604
Entity Address, Address Line One	3200 Kirby Drive, Suite 600
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77098
City Area Code	(713)
Local Phone Number	335-5151
Title of 12(b) Security	Common stock $0.001 par value per share
Trading Symbol	PRO
Security Exchange Name	NYSE
Entity Central Index Key	0001392972
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
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
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		44,392,129
Former Address [Member]
Entity Information [Line Items]
Entity Address, Address Line One
Entity Address, City or Town
Entity Address, State or Province
Entity Address, Postal Zip Code