Discontinued Operations and Other Dispositions - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
	Dec. 31, 2016	Nov. 30, 2015	Dec. 30, 2016	Dec. 31, 2015	Feb. 28, 2014
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Discontinued operations			$ 0	$ 0
Claritas
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net proceeds associated with sale of business	$ 34,000,000
Note receivable associated with sale of business	$ 60,000,000
Note receivable, term	3 years
Gain on sale to other income/(expense), net	$ 14,000,000
Claritas | Receivable Bearing Interest at 3% in Year One
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Note receivable, interest rate	3.00%
Claritas | Receivable Bearing Interest at 5% in Year Two
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Note receivable, interest rate	5.00%
Claritas | Receivable Bearing Interest at 7% in Year Three
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Note receivable, interest rate	7.00%
National Research Group, Inc
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net proceeds associated with sale of business		$ 34,000,000
Gain on sale to other income/(expense), net		$ 18,000,000
Harris Interactive, Inc.
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Business acquisition purchase price, per share					$ 2.04