Comprehensive and Detailed 150 to 250 words of Explanation From Workday Record-to-Report/Course Guide/topics:

The supplier invoices generate operational accounting that follows the configured U.S. GAAP account posting rules. Workday ordinarily records operational journals with a blank book code, placing them in the Common Book. Because IFRS requires a different accounting result, the organization must record only the difference through an adjusting accounting journal assigned to an IFRS-specific book code.

The IFRS reporting book can then combine the blank-book-code operational activity with the IFRS adjustment book code. This produces the IFRS result without duplicating the underlying supplier invoice. A U.S. GAAP-specific adjustment is unnecessary because the operational transaction already represents that treatment. Assigning the adjustment to the blank book code would contaminate the common operational basis and make the IFRS difference appear in every book containing blank activity. Creating parallel U.S. GAAP and IFRS adjustments would also duplicate accounting rather than isolate the reporting-basis difference. Therefore, the required transaction is one adjusting journal using the IFRS-specific book code and the ledger accounts needed to reverse or reclassify the U.S. GAAP treatment. This is the central Workday multi-book design: common operational entries are recorded once, while standard-specific differences are held in separate adjustment book codes.

Official Workday reference: Workday Education - Multi-book ; topics: blank book code, common book, and IFRS adjustment journals.

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