The Association between XBRL Adoption and Market Reactions to Earnings Surprises

This paper investigates whether the adoption of XBRL is associated with market reactions to earnings surprises around 10-Q and 10-K filing dates based on a sample of XBRL filers in all three phases. Our main findings demonstrate that the adoption of XBRL is positively associated with market reactions to earnings surprises around 10-Q and 10-K filing dates only for Phase II, not for Phase I, filers except when a Phase I filer is followed by fewer analysts. The full-sample test shows that the hypothesized effect also exists for Phase III filers, and we observe an increase in market reaction for Phase II filers after their second year of adoption. We believe this study has policy implications and may alleviate firms' concerns regarding the benefits of adopting XBRL. JEL Classifications: M41. Data Availability: All data are publicly available.