Accumulated Other Comprehensive Income (Loss) - Change in component of accumulated comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ (5,849)	$ (2,179)	$ (2,095)
Other comprehensive (loss) before reclassifications	(729)	(1,466)	(424)
Amounts reclassified from accumulated other comprehensive (loss) after tax benefit (expense)	3,077	(2,204)	340
Balance at end of period	(3,501)	(5,849)	(2,179)
Income tax (expense) benefit on postretirement benefits	(1,620)	1,187	(183)
Cumulative Foreign Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(1,748)	(282)	142
Other comprehensive (loss) before reclassifications	(729)	(1,466)	(424)
Amounts reclassified from accumulated other comprehensive (loss) after tax benefit (expense)	0	0	0
Balance at end of period	(2,477)	(1,748)	(282)
Postretirement Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(4,101)	(1,897)	(2,237)
Other comprehensive (loss) before reclassifications	0	0	0
Amounts reclassified from accumulated other comprehensive (loss) after tax benefit (expense)	3,077	(2,204)	340
Balance at end of period	$ (1,024)	$ (4,101)	$ (1,897)