docs: @Override
  	public Statement getDetailInfo(String CorpNum, int ItemCode, String MgtKey,
  			String UserID) throws PopbillException {
  		if (MgtKey == null || MgtKey.isEmpty())
  			throw new PopbillException(-99999999, "관리번호가 입력되지 않았습니다.");
  		
  		return httpget("/Statement/" + ItemCode + "/" + MgtKey + "?Detail",
  					CorpNum, null, Statement.class);
  		
  	}