The Financial Accounting Standards Board (FASB) staff has issued guidance on how to implement Extensible Enumerations (EE) 2.0 in XBRL-formatted reporting. The implementation of EE 2.0 will begin with the 2021 US GAAP Financial Reporting and SEC Reporting (SRT) taxonomies.
Extensible enumerations are designed to improve data usability. They were first introduced by FASB as a custom type in 2017, and in early 2020, the XBRL International Standards Board formally recommended EE 2.0. However, the EE 2.0 recommendation requires certain changes in XBRL report creation procedures. XBRL reports using the 2021 US GAAP and SRT taxonomies that are submitted to the SEC will need to be modified to properly support EE 2.0. Taxonomy updates such as these are generally available for use in the latter part of the first quarter of each calendar year.
Previously, the US GAAP and SRT taxonomies utilized a custom data type (extensibleListItemType) that partially met the modeling requirements. Now, with EE 2.0 reaching formal recommendation status, all taxonomy elements with that custom data type will be converted to the EE 2.0 data type, enumerationSetItemType. The following requirements must be met for proper instance document validation:
1. The fact value reported must have the proper URI-based notation.
The extensibleListItemType used a space-separated list of QNames. However, the recommendation EE 2.0 specification uses a different URI-based notation for the enumerationSetItemType. The reported facts must now be a space-separated list of unique values that are lexicographically ordered.
2. The element(s) reported as a fact value must exist in a schema.
The element with the enumerationSetItemType must be from a base taxonomy (US GAAP, SRT, and SEC taxonomies) or an extension of these taxonomies. The element must also be xbrli:item substitution group and not in the xbrldt:hypercubeItem or xbrldt:dimensionItem substitution groups.
3. The element(s) reported as a fact value must be present in the domain-member relationships defined in the taxonomies.
EE 2.0 will also have updated data type schema requirements, dated 2020-01-21. This schema includes the new data type of noLangTokenItemType, which is the base data type for the EE 2.0 data types.
When necessary, GoFiler will take these changes into account with little to no effort on the part of the user in the creation of SEC-compliant submissions. Please periodically check software release notes for more information.