Error Parsing UNF's report from 2012 q1

[Mossharbor]

Hello when parsing UNF (CIK 717954) q1 report from 2012.
Link to SEC XBRL
I am getting the following error:
Error in eval(substitute(expr), envir, enclos) : expecting a single value

xbrl_url_unf2012 <- "...../UNF/2012/q1/xbrl/unf-20111126.xml"
old_o <- options(stringsAsFactors = FALSE)
xbrl_data_unf2012 <- xbrlDoAll(xbrl_url_unf2012, verbose = TRUE)
options(old_o)
statement <- xbrl_get_statements(xbrl_data_unf2012)

NOTE: this also fails on their 2013 reports but not their 2014 reports (could be malformed xbrl, but sadly I don't know enough about the format to be sure??)