Share Based Compensation - Outstanding stock units (Details) - Director	12 Months Ended
	Jan. 31, 2021 $ / shares shares
Number of stock units
Outstanding, beginning of period (in shares) | shares	129,413
Granted (in shares) | shares	27,727
Deferred retainers (in shares) | shares	2,330
Dividends (in shares) | shares	1,685
Vested (in shares) | shares	(9,184)
Outstanding, end of period (in shares) | shares	151,971
Weighted average price
Outstanding, beginning of period (in usd per share) | $ / shares	$ 24.95
Granted (in usd per share) | $ / shares	21.46
Deferred retainers (in usd per share) | $ / shares	21.46
Dividends (in usd per share) | $ / shares	21.64
Vested (in usd per share) | $ / shares	21.56
Outstanding, end of period (in usd per share) | $ / shares	$ 24.43