\version "2.14.2"
\paper {
  % change for other default global staff size. 
  myStaffSize = #20
  %{
     run
         lilypond -dshow-available-fonts blabla
     to show all fonts available in the process log.  
  %}

  #(define fonts
    (make-pango-font-tree "Times New Roman"
                          "Nimbus Sans"
                          "Luxi Mono"
     (/ myStaffSize 20)))
}
{ b1-\markup{\italic {détaché}} }