Special Currency Format

Our company has a unique currency reporting format. Thousands are "M", Millions are "MM". I have crafted the format with one small issue. The negative currency does not do the "MM", only "M". Can anyone help me fix this formula? Oh, negatives should also be red and in parenthesis. Currency: [>=1000000] $#,##0.0,," MM";[>0] $#,##0.0," M";[Red]($#,###," M").

I have never got a format to do all of what you ask, so I tend to revert to event code to test the value and set the format accordingly.