Dividends and Treasury Stock Dividends paid (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Stockholders' Equity Note [Abstract]
Payments of Ordinary Dividends, Common Stock	$ 0	$ 4,648	$ 9,318	$ 14,001
Cash dividends paid per common share (in dollars per share)	$ 0	$ 0.130	$ 0.260	$ 0.390
Dividends Payable	$ 0	$ 0	$ 0	$ 0

Aggregate dividends paid during the period for each share of common stock outstanding.

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-Name Accounting Standards Codification
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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

+ References

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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