December has been an incredibly eventful month to close out the year! Alongside our latest technical milestones, the team connected with the broader reporting community at the virtual XBRL International Data Amplified conference. It was a fantastic opportunity to share insights and discuss the evolving landscape of digital financial reporting.

On the development front, we are capping off 2025 with a major milestone release: Arelle 2.38.0 and iXBRL Viewer 1.4.84.

Regulatory & Validation Milestones

• EDGAR 25.4: Full support for the EDGAR 25.4 release is now live.
• ESEF 2025 Draft: You can now prepare for upcoming European filings with our ready-to-use ESEF 2025 draft support.
• EDINET Completion: We have achieved a major landmark with completely finalized EDINET validation support.
• NL NT20 Preview: This update introduces initial preview validation support for the Dutch NT20 taxonomy.

Infrastructure & Code Modernization

• Python 3.14 Alignment: To keep our stack future-proof, both Arelle and the iXBRL Viewer now include initial support for Python 3.14.
• Enhanced Code Quality: Developers will benefit from significant type hint improvements in the core platform, alongside full type hints checking implemented across the iXBRL Viewer for greater stability.

As we look back on a highly productive year, the Arelle team wants to thank all of our users and contributors. Happy holidays, and we wish you all a happy and successful new year!

To get involved with future work, please join the Arelle team monthly standup on the fourth Tuesday of each month at 1400 UTC. Please contact us for meeting details.