Show or hide a LIST based on Parameter value

I have 2 parameters in my report. I have a main section and a list. I want to Hide the list when the parameter A has more than 1 value. Parameters A has values like - ""Department A","Department B", "Department,Test" " etc.(comma separated values- can be a comma between parameter values as well). Please help with the expression.

=IIf(Parameters!A.Value > "1", true, false)