above and beyond the call of duty

[Theseus]

To go above and beyond one's duty or, more commonly, go above and beyond the call of duty
means to exceed what is required of one.
--Doing what you ask goes above and beyond my duty.
--My job requires me to go above and beyond the call of duty almost every day.mg:

 

[Zazula]

In formal contexts:
πέραν του καλώς εννοουμένου καθήκοντος
πέραν της έννοιας του καλώς εννοουμένου καθήκοντος
πέρα από το καλώς εννοούμενο καθήκον

 

[daeman]

Hi Theseus,

For the time being (this year's time at least; what's left of it), two related threads:

go the extra mile
second mile leader

Now I'll have to run; duty calls. Nevertheless, I can afford the time to wish you a happy new year! :)

 

[dharvatis]

I believe that the phrase "above and beyond the call of duty" originates from the citations awarded to members of the Armed Forces, e.g. the Medal of Honor. The corresponding phrase used in Greek medals and citations is the one that Zaz already posted (see for example here).