Assets and Liabilities Held for Sale (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets held for sale	$ 1,133	$ 0
Disposal Group, Including Discontinued Operation, Liabilities, Current	200	0
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	218	$ 142	$ (53)
Specialty Pharmaceuticals [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Consideration	800
Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents	37
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net	24
Disposal Group, Including Discontinued Operation, Inventory, Current	79
Disposal Group, Including Discontinued Operation, Other Assets, Current	17
Disposal Group, Including Discontinued Operation, Goodwill, Current	175
Disposal Group, Including Discontinued Operation, Intangible Assets, Current	758
Disposal Group, Including Discontinued Operation, Other Assets, Noncurrent	45
Assets held for sale	1,133
Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities, Current	25
Disposal Group, Including Discontinued Operation, Other Liabilities, Current	27
Disposal Group, Including Discontinued Operation, Non-current deferred tax liability, Current	148
Disposal Group, Including Discontinued Operation, Liabilities, Current	200
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ 107