Medicare pretty much does not pay outside of the USA, see Medicare & You or Publication 11037 Medicare outside of USA for more details. Medicare Advantage Plans, Medi Gap and Supplements generally will pay up to $50k for up to 2 month visit. Check the EOC – Evidence of Coverage, do not quote anything you read on the internet.
If you are going on a longer trip or need more coverage, check out our International Travel Policies.
See also our page on International Travel.