form 1040 line 2a tax exempt interest/where is there a breakdown?

1040 line 2a comes from 1099Div box 12 Exempt Interest Dividends and maybe K-1 form.  

Also from 1099-INT and 1099-OID.   See IRS 1040 line 2a on page 25

https://www.irs.gov/pub/irs-pdf/i1040gi.pdf