Even though there are examples of HCI practices related to e-Government, bibliographic research revealed a lack of studies regarding the XBRL financial reports area, which is representative of the G2G e-governance. So, there was a missing link between those areas. In this project, the awareness step pointed out technical and HCI demands in the financial reporting area that degrade the efficiency of G2G and G2B e-Governance because some government institutions require private and public entities to submit those XBRL financial reports. So, this research investigated how HCI design can mitigate the presented research problem through a software prototype built under HCI design matters that provides XBRL knowledge abstraction, thus increasing task efficiency and improving G2G e-Governance. This research proved HCI design as a valid approach to increase the XBRL reporting professionals' task efficiency, thus improving G2G e-Governance, and attained other relevant contributions in the HCI and e-Government areas such as: finding the missing link between HCI, G2G e-Governance, and XBRL financial reporting, and other relevant findings.