Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Aug. 09, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2020
Entity File Number	001-37394
Entity Registrant Name	Black Knight, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-5265638
Entity Address, Address Line One	601 Riverside Avenue
Entity Address, City or Town	Jacksonville
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	32204
City Area Code	904
Local Phone Number	854-5100
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	BKI
Security Exchange Name	NYSE
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001627014
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		157,029,927