Javascript – json, denormalize array of object

I have a json object made like this (array of object with array element)

var orders = [
  {
    "employ": {
      "id": "1",
      "name": "1_name",
    },
    "order": [
      {
        "number": "1_1",
        "desc": "1_1_desc"
      },
      {
        "number": "1_2",
        "desc": "1_2_desc"
      }      
    ]
  },
  {
    "employ": {
      "id": "2",
      "name": "2_name",
    },
    "order": [
      {
        "number": "2_1",
        "desc": "2_1_desc"
      }      
    ]
  }  
]

and I have to denormalize it to get this, a simple array of objects

[
  {
    "emp_id": "1",
    "emp_name": "1_name",
    "ord_number": "1_1",
    "ord_desc": "1_1_desc"
  },
  {
    "emp_id": "1",
    "emp_name": "1_name",
    "ord_number": "1_2",
    "ord_desc": "1_2_desc"
  },
  {
    "emp_id": "2",
    "emp_name": "2_name",
    "ord_number": "2_1",
    "ord_desc": "2_1_desc"
  }
]

I use two nested for, but I was wondering if it is possible to do it in another way, perhaps more performing.

var orders_flat = [];
for(var i = 0; i < orders.length; i++) {
  for(var a = 0; a < orders[i].order.length; a++) {
    var o = {};
    o.emp_id     = orders[i].employ.id;
    o.emp_name   = orders[i].employ.name;
    o.ord_number = orders[i].order[a].number;
    o.ord_desc   = orders[i].order[a].desc;
    orders_flat.push(o);
  }
}

TIA