Segment and Geographic Information - Reconciliation of Reportable Segment Assets to Corresponding Consolidated Amounts (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Segment Reporting Information [Line Items]
Cash and cash equivalents, restricted cash, and marketable securities	$ 1,443,424	$ 2,305,081
Deferred tax asset	298	1,169
Other assets	74,975	181,479
Assets	3,292,416	3,716,122
Operating Segments
Segment Reporting Information [Line Items]
Assets	$ 1,773,719	$ 1,228,393