Dividends and Treasury Stock Dividends paid (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Stockholders' Equity Note [Abstract]
Payments of Ordinary Dividends, Common Stock	$ 0	$ 4,660	$ 0	$ 9,318
Dividends Payable	$ 0	$ 0	$ 0	$ 0

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Balance Type:	credit
Period Type:	instant