Loss Per Share - Schedule of Net Loss Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net loss	$ (15,600)	$ (13,057)
Less: Net loss attributable to noncontrolling interests	(3,783)	(4,433)
Net loss attributable to Definitive Healthcare Corp.	(11,817)	(8,624)
Basic net loss per share attributable to common stockholders [Abstract]
Allocation of net loss attributable to Definitive Healthcare Corp.	$ (11,817)	$ (8,624)
Weighted average number of shares of Class A outstanding	108,234,043	97,158,823
Net loss per share, basic	$ (0.11)	$ (0.09)
Net loss per share, diluted	$ (0.11)	$ (0.09)
Common Class A [Member]
Net loss	$ (15,600)	$ (13,057)
Less: Net loss attributable to noncontrolling interests	(3,783)	(4,433)
Net loss attributable to Definitive Healthcare Corp.	(11,817)	(8,624)
Basic net loss per share attributable to common stockholders [Abstract]
Allocation of net loss attributable to Definitive Healthcare Corp.	$ (11,817)	$ (8,624)
Weighted average number of shares of Class A outstanding	108,234,043	97,158,823
Net loss per share, basic	$ (0.11)	$ (0.09)
Net loss per share, diluted	$ (0.11)	$ (0.09)