Related Party Transactions - Summary of Activity Related to Agreements with Related Party (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Related Party Transaction [Line Items]
Earnings from equity investments	$ 1.6	$ 0.4
Distributions received from equity investments	2.6	4.7
LM4
Related Party Transaction [Line Items]
Processing fee incurred	5.0	4.5
Earnings from equity investments	1.6	0.4
Distributions received from equity investments	$ 2.6	$ 4.7

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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