Acquisitions and Dispositions - Narrative (Details) - CareerBuilder - employee	Sep. 02, 2016	Aug. 01, 2016	Mar. 01, 2016
Aurico Inc.
Business Acquisition [Line Items]
Ownership interest acquired (as a percent)			100.00%
DealerRater
Business Acquisition [Line Items]
Ownership interest acquired (as a percent)		100.00%
Workterra LLC
Business Acquisition [Line Items]
Ownership interest acquired (as a percent)	75.00%
Number of employees served by Workterra's cloud based solution, more than	600,000