docs: function calculateMaxLength(value) {
                  var length = 16;
                  if (!angular.isUndefined(value)) {
                      length = Math.floor(value).toString().length;
                  }
                  if (decimals > 0) {
                      // Add extra length for the decimals plus one for the decimal separator.
                      length += decimals + 1; 
                  }
                  if (min < 0) {
                      // Add extra length for the - sign.
                      length++;
                  }
                  return length;
              }