Document and Entity Information shares in Millions	6 Months Ended
	Jun. 30, 2020 shares
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	001-37470
Entity Registrant Name	TransUnion
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	61-1678417
Entity Address, Address Line One	555 West Adams,
Entity Address, City or Town	Chicago,
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60661
City Area Code	312
Local Phone Number	985-2000
Title of 12(b) Security	Common Stock, $0.01 par value
Trading Symbol	TRU
Security Exchange Name	NYSE
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	190.1
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001552033
Current Fiscal Year End Date	--12-31