The data for this study were collected from the Thomson ONE Banker database. For the US, we include all firms listed
on the NYSE and NASDAQ for the eight-year period from 2005 to 2012; that is, four years before and four years after the
XBRL use mandate transpired in the US (see Fig. 1). The SEC implemented a “phase-in” approach (Srivastava and Kogan,
2010) and mandated that publicly listed US firms file their financial statements in XBRL format in accordance with their
market capitalization (i.e. above USD5 billion from June 15, 2009, between USD700 million and USD5 billion from June 15,
2010, and the remaining firms from June 15, 2011) (SEC, 2009). Thus, for the US firms, the 2005–2008 period is denoted as
pre-XBRL and the 2009–2012 period as post-XBRL. After removing voluntary XBRL users4 before 2009 and firms with missing
data, our US data set contains 17,010 firm-year observations.
The Japanese data set includes all firms listed on the TSE for the 2004–2011 period. Because the Japanese FSA mandated that
all publicly listed firms must file their financial statements in XBRL format from April 2008 (Bai et al., 2013; FSA, 2008; Kobayashi,
2008), we consider the four-year pre-XBRL and post-XBRL periods as 2004–2007 and 2008–2011, respectively (see Fig. 1). After
eliminating missing data for the variables, the Japanese data set consists of 7067 firm-year observations.