Receivables and Allowance for Doubtful Accounts - Additional Information (Detail) - USD ($)	Dec. 31, 2021		Dec. 31, 2020		Dec. 31, 2019	[1]	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables	$ 123,189,000		$ 90,521,000
Allowance for doubtful accounts receivables	33,957,000	[1]	36,649,000	[1]	$ 27,130,000		$ 40,164,000
Customers and other	136,345,000		121,261,000
Aggregate carrying amount of other receivables	560,391,000		552,655,000
Customer and Other Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customers and other	122,229,000		99,965,000
Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for doubtful accounts receivables	$ 0		$ 0

[1] The allowance for doubtful accounts balances are substantially all related to M&A and Restructuring fee receivables that include reimbursable expense receivables.