Organization and Summary of Significant Accounting Policies Schedule of Effect of New Accounting Pronouncements (Details) - USD ($) $ in Millions	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Prepaid and other current assets	$ 1,606	$ 1,757	$ 1,661
Other long-term assets	2,555	2,732	2,722
Other accrued liabilities	3,139	3,255	3,370
Other long-term obligations	1,040	589	558
Retained earnings	$ 19,024	19,202	$ 19,012
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] | Accounting Standards Update 2014-09 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Prepaid and other current assets		96
Other long-term assets		10
Other accrued liabilities		(115)
Other long-term obligations		31
Retained earnings		$ 190