0x800a138f JavaScript Error Unable to get undefined or Null in createRange

My aspx

<%@ Register Assembly="Framework.WebControls" Namespace="Framework.WebControls" TagPrefix="cc1" %>
.
.
.
<cc1:CustTextBox ID="txtUserId" CssClass="showWord7" runat="server"   Width="150px"    MaxLength="15" Text=""></cc1:CustTextBox>

run code input data show error only for IE, chrome is success

enter image description here

Error in the paragraph in the figure