Acquisitions (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Payments to Acquire Businesses, Net of Cash Acquired	$ 324	$ 187
Probiotics & Rodelle [Member]
Business Acquisition [Line Items]
Payments to Acquire Businesses, Gross	366
Cash Acquired from Acquisition	42
Business Acquisition, Purchase Price Allocation, Working Capital	(7)
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment	39
Goodwill	165
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	137
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities	(1)
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value	(9)
Payments to Acquire Businesses, Net of Cash Acquired	$ 324