Equity (Details) (Parenthetical) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended
	Jul. 31, 2020	Apr. 30, 2020	Jul. 31, 2019	Apr. 30, 2019	Jul. 31, 2020		Jul. 31, 2019
Dividends per share	$ 0	$ 0	$ 0.20	$ 0.20			$ 0.40
Net unrealized gain (loss) on investments, tax provision/(benefit)	$ 2		$ 2		$ (11)		$ 3
Amortization of prior service cost, tax provision	$ 4		$ 3		8		7
Stock-based compensation expense					3,109	[1]	$ 3,082
Corporate Initiatives
Stock-based compensation expense					$ 400
Common Stock Class Undefined
Common Stock, Voting Rights					Each share of common stock is entitled to one vote per share on all matters submitted to a vote of the shareholders.
Class A Common Stock
Common Stock, Voting Rights					Each share of common stock is entitled to one vote per share on all matters submitted to a vote of the shareholders.
Common stock, Conversion basis					Each share of class A common stock is entitled to 10 votes per share on all matters submitted to a vote of the shareholders. Each holder of class A common stock is entitled to convert, at any time, any and all of such shares into the same number of shares of common stock. Each share of class A common stock is converted automatically into common stock in the event that the beneficial or record ownership of such shares of class A common stock is transferred to any person, except to certain family members or affiliated persons deemed “permitted transferees” pursuant to the Company’s Restated Certificate of Incorporation, as amended.

[1] Includes $0.4 million related to the Restructuring Plan of the corporate initiatives.