Supplemental Cash Flow Information - Supplemental Cash Flow Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Supplemental Cash Flow Information:
Interest paid	$ 124	$ 82	$ 94
Income taxes paid, net of refunds	106	121	$ 139
Non-cash Investing Activities:
Fair value of consideration transferred in connection with business combinations	$ 10,425	$ 423