Visa transit in shanghai airport

Part one:

If your itinerary is:

US - Shanghai - Indonesia (Denpasar)

And you don't have any additional landing within mainland China of any kind, you will be eligible for 24 hour visa free transit and you don't need any kind of visa.

You will print out your flight tickets and have those printouts with you all the time. You will also declare at check-in in US that you will travel to Indonesia (Denpasar) via China (Shanghai) using 24 hour visa free transit. After a short check of your flight tickets, you will be allowed to board the plane. Also and this is very important, you will ask at check-in in US whether your luggage will be tagged all the way to Indonesia (Denpasar). If you are traveling on a single (through) ticket by China Eastern all the way to Indonesia, you luggage will be tagged to Indonesia almost for certain, but you will ask about this detail, just for a case.

Part two:

Upon your landing in Shanghai, you can choose whether you will remain at the airport and this is perfectly fine or you can try to obtain a temporary entry permit to be allowed to exit the airport. If you want to exit the airport, you are advised to book some simple accommodation in Shanghai because without the accommodation, you will bot be allowed to exit the airport. So, if you want to try to exit the airport, you should book your accommodation while still in US. You will also bring a printout of your accommodation booking, ready to be presented to Chinese immigration authorities.

So, if you decide to try to exit the airport, you will immediately approach 24 hour visa free transit counter upon your landing in Shanghai where you will apply for a temporary entry permit that is free of charge. You will present your flight tickets and also your accommodation booking confirmation. Since your layover is very long and during the entire night, your chances are very good to be granted a temporary entry permit, but you should also have in mind that the issuing of the mentioned permit is always upon discretion of immigration authorities on a day of arrival.

If you are granted a temporary entry permit, you will exit the airport. Withe the approaching of the time of your flight, you will go to the airport and you don't need to make any check-in, especially if your luggage is tagged all the way to Indonesia and if you are holding two boarding passes or better to say a boarding pass for a flight to Denpasar. You will just approach to security and after you clear an immigration, you will just proceed to the boarding gate of your flight to Indonesia.