Is this the link you are looking for?
http://ssa.gov/pubs/10137.html#when

When you are “outside the United States
"When we say you are outside the United States, we mean you are not in one of the 50 states, the District of Columbia, Puerto Rico, the U.S. Virgin Islands, Guam, the Northern Mariana Islands or American Samoa. Once you have been out of the United States for at least 30 days in a row, you are considered to be outside the country until you return and stay in the United States for at least 30 days in a row. If you are not a U.S. citizen, you also may have to prove you were lawfully present in the United States for that 30-day period."


What happens to your right to Social Security payments when you are outside the United States
"If you are a U.S. citizen, you may receive your Social Security payments outside the United States as long as you are eligible for them.

However, there are certain countries to which we are not allowed to send payments."


I have never notified SS when I have traveled abroad for 2 months. Been traveling abroad for years while collecting SSDI. Since my $$$$ are directly deposited in a bank within the USofA, I see no reason to notify them unless I plan on living abroad in the future.