Dividends and Treasury Stock Dividends paid (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2021	Apr. 30, 2020
Stockholders' Equity Note [Abstract]
Payments of Ordinary Dividends, Common Stock	$ 0	$ 4,658
Dividends Payable	$ 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
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
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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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant