Long-lived Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets	$ 103,899	$ 121,908
United States
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets	98,985	114,119
Canada
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets	3,653	6,654
Colombia
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets		1
Russian Federation
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets	689	717
United Kingdom
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets	559	404
China
Schedule Of Long Lived Assets [Line Items]
Long-lived assets, excluding deferred tax assets	$ 13	$ 13