What is Nirvana (mahayana)?

...as per the title. In the Theravada literature, the Buddha is seen as someone who found an end to suffering and taught that for all his life, urging his disciples to apply themselves to it, to not waste the opportunity and regret later. While there are many interpretations of what exactly is Nirvana in this tradition (and what is/is-not a tathagata after death etc), it's perhaps universally accepted by it's adherents that embarking on this doctrine culminates in the permanent cessation of suffering. Some may speculate or say more about Nirvana, but others might be silent and not add anything that the texts don't say. But what about Mahayana's Nirvana? * Is it the same same? Or is it more elaborated, like a realm where beings (Buddhas?) actually live? * Does it have the same requirements as the Theravada nirvana (e.g. elimination of the ten fetters, realization of four noble truths & dependent origination)?