diff --git a/quickbooks/client.py b/quickbooks/client.py
index b3acf68e..77eb77cb 100644
--- a/quickbooks/client.py
+++ b/quickbooks/client.py
@@ -243,11 +243,11 @@ def handle_exceptions(self, results):
             message = error["Message"]
 
             detail = ""
-            if "Detail" in error:
+            if "Detail" in error and error["Detail"] != 'null':
                 detail = error["Detail"]
 
-            code = ""
-            if "code" in error:
+            code = 0
+            if "code" in error and error["code"] != 'null':
                 code = int(error["code"])
 
             if code >= 10000:
diff --git a/quickbooks/mixins.py b/quickbooks/mixins.py
index c4df8cc0..48352915 100644
--- a/quickbooks/mixins.py
+++ b/quickbooks/mixins.py
@@ -45,7 +45,7 @@ def from_json(cls, json_data):
                     sub_list.append(sub_obj)
 
                 setattr(obj, key, sub_list)
-            else:
+            elif key in vars(obj):
                 setattr(obj, key, json_data[key])
 
         return obj
diff --git a/quickbooks/objects/detailline.py b/quickbooks/objects/detailline.py
index 9f852883..168aeb2b 100644
--- a/quickbooks/objects/detailline.py
+++ b/quickbooks/objects/detailline.py
@@ -220,7 +220,7 @@ class ItemBasedExpenseLineDetail(QuickbooksBaseObject):
 
     def __init__(self):
         super(ItemBasedExpenseLineDetail, self).__init__()
-        self.BillableStatus = ""
+        self.BillableStatus = None
         self.UnitPrice = 0
         self.TaxInclusiveAmt = 0
         self.Qty = 0
diff --git a/quickbooks/objects/invoice.py b/quickbooks/objects/invoice.py
index da615cdf..59aeb8b3 100644
--- a/quickbooks/objects/invoice.py
+++ b/quickbooks/objects/invoice.py
@@ -60,6 +60,7 @@ def __init__(self):
         self.AllowIPNPayment = True
         self.DocNumber = ""
         self.PrivateNote = ""
+        self.TxnDate = ""
         self.DueDate = ""
         self.ShipDate = ""
         self.TrackingNum = ""
diff --git a/quickbooks/objects/salesreceipt.py b/quickbooks/objects/salesreceipt.py
index 91ff18e8..65dcef69 100644
--- a/quickbooks/objects/salesreceipt.py
+++ b/quickbooks/objects/salesreceipt.py
@@ -2,7 +2,7 @@
 from .base import Ref, CustomField, QuickbooksManagedObject, LinkedTxnMixin, Address, \
     EmailAddress, QuickbooksTransactionEntity, LinkedTxn
 from .tax import TxnTaxDetail
-from .detailline import DetailLine
+from .detailline import DetailLine, SalesItemLine
 from ..mixins import QuickbooksPdfDownloadable, DeleteMixin
 
 
@@ -37,7 +37,7 @@ class SalesReceipt(DeleteMixin, QuickbooksPdfDownloadable, QuickbooksManagedObje
     }
 
     detail_dict = {
-
+        "SalesItemLineDetail": SalesItemLine
     }
 
     qbo_object_name = "SalesReceipt"