Significant Accounting Policies Significant Accounting Policies (Details) - USD ($) $ in Millions		12 Months Ended
	Jan. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2018	Jan. 01, 2018
Significant Accounting Policies [Line Items]
Selling, general and administrative expenses		$ 3,941	$ 3,569	$ 3,294
Percent of finished goods at consignment		32.00%	40.00%
Concentration Risk, Customer		0	0	0
Other Liabilities, Current		$ 800	$ 412
Other Liabilities, Noncurrent		2,635	1,882
Other Assets, Noncurrent		1,529	845
Deferred Tax Liabilities, Noncurrent		595	328
Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Selling, general and administrative expenses		$ 144	124	$ 110
Adjustments for New Accounting Pronouncement [Member]
Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						$ 177
Accounting Standards Update 2016-16 [Member]
Significant Accounting Policies [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption					$ 55
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Significant Accounting Policies [Line Items]
Other Liabilities, Current			59
Other Liabilities, Noncurrent			205
Other Assets, Noncurrent			12
Deferred Tax Liabilities, Noncurrent			$ (41)
Operating lease, right-of-use assets, other long-term assets [Member] | Accounting Standards Update 2016-02 [Member]
Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 271
Operating lease, liability, other long-term liabilities [Member] | Accounting Standards Update 2016-02 [Member]
Significant Accounting Policies [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 278