Move my digital piano back home

Dear everyone,
I bought a digital piano in Japan and now I want to carry it back to my country. Does the airline in Japan allow me to handcarry it on plane? If it is impossible, what is the best way to send it back?
My piano is about 20 kg with dimension 1330 x 355 x 133 mm
Please advice me how to do in this case. (attaching estimated cost will be more helpful)
Thanks for your help.

You can check with your airline for its hand carry policy. There is the limit on the dimensions and weight, obviously. You would be paying extra for that additional cargo, though. If the airline says they cannot carry your piano, contact Nippon Express (or Nittsu) or other freight companies to process the "personal effect" shipment.

Are you asking if you can hand carry into the cabin or put it in your checked baggage? Don't know about the first case, but you can certainly have it be checked baggage. Airlines charge extra if it's over 62 linear inches (height+length+width), which your keyboard is. So expect to pay a fee (probably around 7500-15000 Yen) if checked. Because of the size, if you tried to bring it in the cabin they'd probably try to charge you an extra seat to fly it. Checked would certainly be cheaper.

FYI, I have flown to/from Japan many times with my bicycle. Never had a problem with it in terms of damage. It's a $4000+ bike, and I don't ever worry about damage.

Thank all of you guys! m(_)m
I love it very much so I do not want to resell it.