Leases (Tables)

12 Months Ended

Sep. 30, 2021

Leases [Abstract]

Lease Costs

Table 12.1: Details of Lease Costs
	For the Year Ended September 30,
	2021		2020
	(in thousands)
Operating lease cost	$	111,246	$	102,811
Short-term lease cost	7,044		9,140
Variable lease cost	11,124		13,310
Total operating lease costs	$	129,414	$	125,261

Future Minimum Lease Payments

Table 12.2: Future Minimum Lease Payments Under Non-cancelable Operating Leases
	Office Space		Equipment		Total
	(in thousands)
Year ended September 30, 2022	$	78,222	$	4,067	$	82,289
Year ended September 30, 2023	50,281		678		50,959
Year ended September 30, 2024	30,870		121		30,991
Year ended September 30, 2025	23,540		11		23,551
Year ended September 30, 2026	10,035		2		10,037
Thereafter	13,568		—		13,568
Total minimum lease payments	206,516		4,879		211,395
Less: Imputed interest	(13,418)		(129)		(13,547)
Total lease liabilities	$	193,098	$	4,750	$	197,848