Share capital - Stock units plans and changes (Details)	3 Months Ended
	Feb. 29, 2020 shares
Number of RSU's [Member]
Balance - beginning of the year	212,501
Vested/paid	(212,501)
Number of DSU's [Member]
Balance - beginning of the year	1,137,488
Granted	21,927
Vested/paid	0
Balance - end of period	1,159,415