Product Revenues, Net, Accounts Receivable, Net, and Reserves for Product Revenues - Summary of Change in Reserves for Discounts and Allowances (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Accounts Notes And Loans Receivable [Line Items]
Beginning balance	$ 164,772	$ 94,698
Provision	258,176	175,967
Adjustments relating to prior periods	(8,021)	(4,044)
Payments/credits	(249,433)	(133,337)
Ending balance	165,494	133,284
Chargebacks [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance	27,486	417
Provision	72,832	18,191
Adjustments relating to prior periods	783	110
Payments/credits	(77,808)	(9,386)
Ending balance	23,293	9,332
Rebates [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance	98,194	67,493
Provision	118,228	94,025
Adjustments relating to prior periods	(8,716)	(4,154)
Payments/credits	(100,693)	(73,317)
Ending balance	107,013	84,047
Prompt Pay [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance	3,831	3,343
Provision	13,442	11,251
Adjustments relating to prior periods	0	0
Payments/credits	(12,191)	(10,586)
Ending balance	5,082	4,008
Other Accruals [Member]
Accounts Notes And Loans Receivable [Line Items]
Beginning balance	35,261	23,445
Provision	53,674	52,500
Adjustments relating to prior periods	(88)	0
Payments/credits	(58,741)	(40,048)
Ending balance	$ 30,106	$ 35,897