Acquisitions Acquisitions - Summary of Exited Space Liability (Details) - CEB - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2017	Jun. 30, 2017
Liability Related to Exited Space [Roll Forward]
Beginning liability balance	$ 20,149	$ 0
Charges and adjustments during the period	974	20,149
Ending liability balance	$ 21,123	$ 20,149

Business Combination Separately Recognized Transactions, Liabilities Recognized [Roll Forward]

No definition available.

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- Definition

The expenses and losses recorded for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The amount of liabilities recognized recorded in a transaction with the acquiree for each transaction that is recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

+ References

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