Direct contribution to profit minus allocated shared services and administrative costs.

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Segment Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
Segment Information (Details) $ in Thousands	Apr. 30, 2018 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Jul. 31, 2017 USD ($)	Apr. 30, 2017 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)	Jul. 31, 2016 USD ($)	Apr. 30, 2018 USD ($) Segment	Apr. 30, 2017 USD ($)	Apr. 30, 2016 USD ($)
Segment Information [Abstract]
Number of reportable segments \| Segment									3
Segment Reporting Information [Line Items]
Revenue	$ 477,300	$ 455,700	$ 451,700	$ 411,400	$ 452,200	$ 436,400	$ 425,600	$ 404,300	$ 1,796,103	$ 1,718,530	$ 1,727,037
Corporate Expenses									(181,961)	(186,600)	(194,047)
Operating Income	$ 74,800	$ 67,400	$ 82,800	$ 14,500	$ 63,500	$ 51,200	$ 47,700	$ 43,800	239,535	206,153	188,113
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenue									1,796,103	1,718,530	1,727,037
Contribution to Profit									421,496	392,753	382,160
Operating Segments [Member] \| Research [Member]
Segment Reporting Information [Line Items]
Revenue									934,395	853,489	826,778
Contribution to Profit									275,480	252,228	252,110
Operating Segments [Member] \| Publishing [Member]
Segment Reporting Information [Line Items]
Revenue									617,648	633,449	695,728
Contribution to Profit									123,917	125,703	126,058
Operating Segments [Member] \| Solutions [Member]
Segment Reporting Information [Line Items]
Revenue									244,060	231,592	204,531
Contribution to Profit									$ 22,099	$ 14,822	$ 3,992