XML 40 R29.htm IDEA: XBRL DOCUMENT v3.8.0.1
Accounting Policies - Accounting Pronouncements Recently Adopted (Details) - USD ($)
$ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Mar. 31, 2018
Mar. 31, 2017
Jan. 01, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]          
Net Cash Provided by (Used in) Operating Activities $ (1,791) $ (1,619) $ 18,194 $ 17,547  
Net Cash Provided by (Used in) Investing Activities (533) (1,350) (26,265) (10,210)  
Net Cash Provided by (Used in) Financing Activities (2,164) (888) 8,653 (3,608)  
Net change in cash, cash equivalents, and restricted cash   (3,857)   3,729  
Accounting Standards Update 2014-09 [Member]          
New Accounting Pronouncements or Change in Accounting Principle [Line Items]          
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets         $ 650
Accounting Standards Update 2016-16 [Member]          
New Accounting Pronouncements or Change in Accounting Principle [Line Items]          
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets $ 250   $ 250    
Accounting Standards Update 2016-18 [Member]          
New Accounting Pronouncements or Change in Accounting Principle [Line Items]          
Net Cash Provided by (Used in) Operating Activities   (29)   (87)  
Net Cash Provided by (Used in) Investing Activities   266   588  
Net Cash Provided by (Used in) Financing Activities   26   49  
Net change in cash, cash equivalents, and restricted cash   263   550  
Scenario, Previously Reported [Member]          
New Accounting Pronouncements or Change in Accounting Principle [Line Items]          
Net Cash Provided by (Used in) Operating Activities   (1,590)   17,634  
Net Cash Provided by (Used in) Investing Activities   (1,616)   (10,798)  
Net Cash Provided by (Used in) Financing Activities   (914)   (3,657)  
Net change in cash, cash equivalents, and restricted cash   $ (4,120)   $ 3,179