Retirement plans Reconciliation of benefit obligations, plan assets and funded status (Details) - USD ($)	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Defined benefit plan vested benefit obligation	$ 6,587,000	$ 7,626,000
Defined Benefit Plan, Accumulated Benefit Obligation	7,020,000	8,129,000
Defined Benefit Plan, Benefit Obligation	7,020,000	8,129,000	$ 6,827,000
Service cost	0	0
Interest cost	266,000	299,000
Actuarial (gain) loss	(1,115,000)	1,249,000
Benefits paid	(260,000)	(246,000)
Defined Benefit Plan, Fair Value of Plan Assets	5,883,000	6,168,000	$ 6,351,000
Defined benefit -plan, actual gain on plan assets	(25,000)	63,000
Unfunded status	(1,137,000)	(1,961,000)
Defined benefit plan, current assets	326,000	352,000
Defined benefit plan, assets for plan benefits, other assets	1,166,000	1,163,000
Defined benefit plans, other long-term liabilities	(2,629,000.00)	(3,476,000)
Defined benefit plan, net amount recognized	(1,137,000)	(1,961,000)
OCI unrecognized actuarial loss	2,303,000	3,124,000
OCI net amount recognized	$ 2,303,000	$ 3,124,000