JQuery change on click

I am trying to make a minus sign back into a plus sign after the user has closed the consumable text.

Here is the HTML code

<p class="textDropTitle"><span class="textDropLogo"></span>Title</p>
    <div class="textDropSub"><p>This is my text Below</div>
    <p class="textDropTitle"><span class="textDropLogo">+</span>Title</p>
    <div class="textDropSub"><p>This is my text Below</div>
    <p class="textDropTitle"><span class="textDropLogo">+</span>Title</p>
    <div class="textDropSub"><p>This is my text Below</div>

      

        
        
        
      

    

JQuery

$(".textDropSub").hide();

$('.textDropLogo', this).text('+');

$(".textDropTitle").click(function() {
    $(this).next().toggle('fast');
    $('.textDropLogo', this).text('-');
});