Goodwill and Intangible Assets, Goodwill (Details) - USD ($) $ in Thousands		9 Months Ended
		Jan. 31, 2022	Apr. 30, 2021
Activity in Goodwill by Segment [Roll Forward]
Balance, beginning of period	[1]	$ 1,304,340
Acquisitions	[2]	42,871
Foreign translation adjustment		(21,247)
Balance, end of period		1,325,964
Cumulative pretax noncash goodwill impairment			$ 110,000
Research Publishing & Platforms [Member]
Activity in Goodwill by Segment [Roll Forward]
Balance, beginning of period	[1]	619,203
Acquisitions	[2]	21,252
Foreign translation adjustment		(12,443)
Balance, end of period		628,012
Academic & Professional Learning [Member]
Activity in Goodwill by Segment [Roll Forward]
Balance, beginning of period	[1]	512,512
Acquisitions	[2]	0
Foreign translation adjustment		(8,243)
Balance, end of period		504,269
Education Services [Member]
Activity in Goodwill by Segment [Roll Forward]
Balance, beginning of period	[1]	172,625
Acquisitions	[2]	21,619
Foreign translation adjustment		(561)
Balance, end of period		$ 193,683

[1] The Education Services goodwill balance as of April 30, 2021 includes a cumulative pretax noncash goodwill impairment of $110.0 million.

[2] Refer to Note 3, “Acquisitions,” for more information related to the acquisitions that occurred in the nine months ended January 31, 2022.