JFK-TXL-JFK route will be the updated 767-300ER (aka 76T), with the new BusinessElite seats and AVOD in Economy. The AVOD will be identical to all other AVOD on the rest of Delta's fleet.
JFK-MAD is operated by an updated 767-400ER, which will have the updated BUsinessElite seats. AVOD will be the same.
You can always look at your reservation at delta.com and it will show amenities, including lay-flat seats.