Revenue - Revenue by Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue from External Customer [Line Items]
Revenue	$ 1,786	$ 1,584	$ 4,868	$ 4,586
Other pharmaceuticals
Revenue from External Customer [Line Items]
Revenue	208	196	597	573
UNITED STATES
Revenue from External Customer [Line Items]
Revenue	996	844	2,605	2,342
AUSTRALIA
Revenue from External Customer [Line Items]
Revenue	60	53	154	150
BRAZIL
Revenue from External Customer [Line Items]
Revenue	62	72	181	206
CANADA
Revenue from External Customer [Line Items]
Revenue	50	47	144	142
CHINA
Revenue from External Customer [Line Items]
Revenue	66	40	198	156
FRANCE
Revenue from External Customer [Line Items]
Revenue	29	24	82	83
GERMANY
Revenue from External Customer [Line Items]
Revenue	38	35	112	111
ITALY
Revenue from External Customer [Line Items]
Revenue	28	26	63	82
JAPAN
Revenue from External Customer [Line Items]
Revenue	39	39	133	118
MEXICO
Revenue from External Customer [Line Items]
Revenue	26	29	84	87
SPAIN
Revenue from External Customer [Line Items]
Revenue	31	29	83	86
UNITED KINGDOM
Revenue from External Customer [Line Items]
Revenue	44	46	125	145
Other Developed Markets [Member]
Revenue from External Customer [Line Items]
Revenue	105	98	282	269
Other Emerging Markets [Member]
Revenue from External Customer [Line Items]
Revenue	165	161	490	482
Total geographical area
Revenue from External Customer [Line Items]
Revenue	1,763	1,565	4,808	4,523
Contract Manufacturing and Human Health Diagnostics [Member]
Revenue from External Customer [Line Items]
Revenue	23	19	60	63
CHILE
Revenue from External Customer [Line Items]
Revenue	$ 24	$ 22	$ 72	$ 64