XML 153 R141.htm IDEA: XBRL DOCUMENT
v3.25.2

Key Management Personnel - Additional Information (Details) - USD ($) | 12 Months Ended
--- | ---
Jun. 30, 2025 | Jun. 30, 2024
Director and Key Management Personnel |  |
Disclosure Of Transactions Between Related Parties [Line Items] |  |
Related party transactions | $ 0 | $ 0

X
- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
Name: | ifrs-full_DisclosureOfTransactionsBetweenRelatedPartiesLineItems
Namespace Prefix: | ifrs-full_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Related party transactions. + References No definition available. + Details
Name: | opt_RelatedPartyTransactions
Namespace Prefix: | opt_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | ifrs-full_CategoriesOfRelatedPartiesAxis=opt_DirectorAndKeyManagementPersonnelMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |