#include <bits/stdc++.h>
using namespace std;
vector<int> FillHalf(const long long W, const vector<int>& w) {
  const long long target = (W + 1) / 2;
  vector<pair<int, int>> items;
  items.reserve(w.size());
  for (int i = 0; i < w.size(); ++i) items.emplace_back(w[i], i + 1);
  sort(items.begin(), items.end());
  auto guess =
      lower_bound(items.begin(), items.end(), target,
                  [](const pair<int, int>& item, const long long x) -> bool {
                    return item.first < x;
                  });
  if (guess != items.end() && target <= guess->first && guess->first <= W)
    return vector<int>{guess->second};
  long long total = 0;
  vector<int> selected_items;
  for (const pair<int, int> item : items) {
    total += item.first;
    selected_items.push_back(item.second);
    if (target <= total && total <= W) return selected_items;
  }
  throw logic_error("IMPOSSIBLE");
}
int main(int argc, char* argv[]) {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  int T;
  cin >> T;
  for (int t = 0; t < T; ++t) {
    int n;
    long long W;
    cin >> n >> W;
    vector<int> w;
    w.reserve(n);
    for (int i = 0; i < n; ++i) {
      w.emplace_back();
      cin >> w.back();
    }
    try {
      vector<int> items = FillHalf(W, w);
      cout << items.size() << '\n';
      copy(items.begin(), items.end(), ostream_iterator<int>(cout, " "));
    } catch (const logic_error& e) {
      cout << -1;
    }
    cout << '\n';
  }
  cout << flush;
  return 0;
}
