What does the idiom “tipped off his rocker” mean?

if you say that someone is off their rocker it means that person is behaving in a strange matter or a very silly way

It could mean a person has gone astray from sanity.

after the signature of the treaty of versailles in june 1919, germany lost nearly 25,000 square miles and a population of 7 million people. these territories included eupen-malmedy area and moresnet which were ceded to belgium. regarding relations with france, germany ceded the sovereignty of the saar coal mines to this country, as well as the provinces of alsace-lorraine.

explanation: