Business Combinations - Other Information (Details) - USD ($) $ in Thousands				12 Months Ended
	Oct. 01, 2021	Jun. 07, 2021	Mar. 02, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2022
Business Combinations
Goodwill arising in the acquisition				$ 703,371	$ 518,592	$ 514,996
Revenue				286,104	243,530	208,511
Net loss				(13,266)	$ (49,397)	$ (8,926)
Author! B.V.
Business Combinations
Business consideration transferred			$ 2,667
Goodwill arising in the acquisition			1,200
Insight Medical Writing Limited
Business Combinations
Business consideration transferred		$ 15,197
Goodwill arising in the acquisition		4,700
Pinnacle 21, LLC
Business Combinations
Business consideration transferred	$ 339,075
Goodwill arising in the acquisition	$ 180,947
Equity acquired (as percentage)	100.00%
Discount for lack of mobility (as percentage)	7.00%
Revenue				6,129
Net loss				$ 380
Integrated Nonclinical Development Solutions, Inc. | Subsequent Events
Business Combinations
Goodwill arising in the acquisition							$ 7,078
General and administrative expenses | Pinnacle 21, LLC
Business Combinations
Acquisition related costs	$ 7,615
Customer relationships | Author! B.V.
Business Combinations
Finite-lived intangible assets acquired			1,200
Customer relationships | Insight Medical Writing Limited
Business Combinations
Finite-lived intangible assets acquired		$ 7,400
Non-compete agreements | Author! B.V.
Business Combinations
Finite-lived intangible assets acquired			$ 100