Comprehensive income (Details Textual) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2012	Jan. 31, 2011
Comprehensive income (Textual) [Abstract]
Pension and postretirement benefit plan adjustment	$ 114,340	$ 101,234
Foreign currency translation adjustment, net	$ 28,686	$ 29,646

The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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+ Details

- Definition

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

+ References

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+ Details