Significant Accounting Policies - Foreign Currency Translation (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Accounting Policies [Abstract]
Net Foreign Currency Loss (Gain) Due to Revaluation	$ (300)	$ 5,525	$ 4,932

The net foreign currency gains (losses) (pretax) included in determining net income due to remeasuring balances into the functional currencies as of the balance sheet date as a result of revaluation.

No definition available.

Name:	azpn_NetForeignCurrencyLossGainDueToRevaluation
Namespace Prefix:	azpn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration