Business Combination, Asset Acquisitions, and Disposition - Celator Acquisition Narrative (Details) - USD ($)			12 Months Ended
	Jul. 12, 2016	Jun. 18, 2015	Dec. 31, 2018	Dec. 31, 2016	Jun. 07, 2018	Jul. 11, 2016	May 27, 2016
Credit Agreement June 2015 Amendment | Borrowings under revolving credit facility
Business Acquisition [Line Items]
Line of credit, maximum borrowing capacity	$ 1,250,000,000				$ 1,600,000,000
Proceeds from revolving credit facility	1,000,000,000
Credit Agreement June 2015 | Term Loan
Business Acquisition [Line Items]
Face amount	$ 750,000,000	$ 750,000,000			$ 667,700,000	$ 750,000,000
Credit Agreement June 2015 | Borrowings under revolving credit facility
Business Acquisition [Line Items]
Line of credit, maximum borrowing capacity		750,000,000				$ 750,000,000
Proceeds from revolving credit facility		$ 160,000,000
Celator Pharmaceuticals, Inc.
Business Acquisition [Line Items]
Share price (in dollars per share)	$ 30.25						$ 30.25
Number of shares tendered during offer period in accordance with merger agreement (in shares)	36,516,173
Percentage of acquiree shares tendered during offer period (as a percent)	81.00%
Offer condition, percentage of common shares tendered (as a percent)	50.00%
Number of acquiree shares delivered via notices of guaranteed delivery in accordance with merger agreement (in shares)	2,016,237
Percentage of acquiree shares delivered via notices of guaranteed delivery in accordance with merger agreement (as a percent)	4.00%
Total acquisition consideration	$ 1,500,000,000
Acquisition-related costs				$ 10,000,000
Intangible assets	1,811,250,000
Celator Pharmaceuticals, Inc. | Acquired IPR&D assets
Business Acquisition [Line Items]
Acquired IPR&D assets	$ 1,800,000,000
Acquired developed technologies
Business Acquisition [Line Items]
Intangible assets, useful life			13 years 11 months 6 days
Acquired developed technologies | Vyxeos
Business Acquisition [Line Items]
Intangible assets, useful life			18 years