Goodwill and Acquired Intangible Assets - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2016	Jul. 01, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Goodwill, acquired during period	$ 11	$ 11
Discontinued Operations, Held-for-sale | Marketing Applications
Finite-Lived Intangible Assets [Line Items]
Goodwill			$ 57	$ 113
Acquired intangibles, net			$ 25	$ 44