Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions			12 Months Ended
Jul. 06, 2020	Jul. 05, 2020	Dec. 31, 2021
Payments for IPO and private placement offering costs	$ 131.9	$ 0.9	$ 132.8

Payments for Underwriting Expense and Stock Issuance Costs

No definition available.

Name:	dnb_PaymentsForUnderwritingExpenseAndStockIssuanceCosts
Namespace Prefix:	dnb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration