hvad gør jeg galt "overflow"

Bygger en side med CSS og i<div> indhold vil jeg lave et overflow men når jeg sætter in koden i CSS rykker højre kolonen ind i indhold istedetfor, hvad er galt.

her er CSS koden til siden.

body {
  font-family:Verdana,Tahoma,Arial,Sans-Serif;
    font-size:10px;
    padding:0px 0px 0px 0px;
    background: #8E9886;color:#000000;
    text-decoration:none;
scrollbar-face-color:#9EB09B;
scrollbar-highlight-color:#CBCFD3;
scrollbar-3dlight-color:#7D897B;
scrollbar-darkshadow-color:#7D897B;
scrollbar-shadow-color:#B4C7B0;
scrollbar-arrow-color:#63774F;
scrollbar-track-color:#ADB9A2;
}
  #banner h1 {
  font-size:14px;
  }
  #indhold {
    margin: 10px 170px 10px 170px;
    border-style: solid;
    border-color: #62784C;
    border-width: 2px 2px 2px 2px;
    background: #ADB9A2;
    min-width: 500px;
    height: 400px;
    text-align: center;
   
       
}

  #indhold h1, #indhold p, #indhold pre {
  margin:0px;
  text-align: center;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 12px;
 
}
  #leftcol {
  width:150px;
  float:left;
  }
  #leftcol p{
    margin:10px;
  }
  .leftbox {
  width:150px;
  float:left;
  background-color:#CCCC99;
  margin:0 0 10px 0;
  font-family:arial,helvetica,sans-serif;
  font-size:12px;
  border-style: solid;
  border-color: #62784C;
  border-width: 2px 2px 2px 2px;
  }
  .leftbox p {
    font-size: 12px;
   
    margin: 10px;
    text-align: left;
}

  #rightcol {
  position:absolute;
  right:10px;
  width:150px;
  top:95px
  }
  .rightbox {
  width:150px;
  background-color:#CCCC99;
  border-width:1px 2px 2px 1px;
  border-style: solid;
    border-color: #62784C;
    border-width: 2px 2px 2px 2px;
    font-size:12px;
  }
  .rightbox p {
  font-size:12px;
  margin:10px;
  }
 
  #rightcol2 {
  position:absolute;
  right:10px;
  width:150px;
  top:195px
  }
  .rightbox2 {
  width:150px;
  background-color:#CCCC99;
  border-width:1px 2px 2px 1px;
  border-style: solid;
    border-color: #62784C;
    border-width: 2px 2px 2px 2px;
    font-size:12px;
  }
 
 
  h4 {
    font-size: 12px;
    color: #62784C;
    margin: 0;
    padding: 5px 10px;
    background-color:#ADB9A2;
    text-align: left;
}



address {
background-color:#CCCC99;
margin:1px;
padding:5px 0 5px 10px;
font-style:normal;font-size:12px;
text-align: center;
border-style: solid;
    border-color: #62784C;
    border-width: 2px 2px 2px 2px;
}

address a {font-size:12px;}

.manchet {
width:350px;
background:white;
margin-left:10px;
}
.manchet p{
font-family:serif;
font-size:14px;
}
  a {font-family:arial,helvetica,sans-serif;
  font-size:11px;
  text-decoration:none;
  font-weight: bold;
  color: #62784C;
}
a:hover        {
    color: Red;
    text-decoration: none;
}

  h1 {font-family:arial,helvetica,sans-serif;
  font-size:24px;}
  h2 {font-family:arial,helvetica,sans-serif;
  font-size:20px;}