Goodwill and Identifiable Intangible Assets - Narrative (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) reportingUnit	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Goodwill [Line Items]
Number of reporting units | reportingUnit		2
Goodwill impairment		$ 238,200,000	$ 0	$ 0
Impairment of intangible assets	$ 18,700,000	18,726,000	4,075,000	0
Amortization expense		3,600,000	$ 6,300,000	$ 7,900,000
MCM
Goodwill [Line Items]
Goodwill impairment		0
Cabot
Goodwill [Line Items]
Goodwill impairment		$ 238,200,000