v3.7.0.1
Employee Stock and Savings Plans - Additional Information (Detail) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
6 Months Ended 12 Months Ended 18 Months Ended
Dec. 31, 2015
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2017
Compensation Related Costs Disclosure [Line Items]          
Company contribution amount for each dollar a participant contributes to the savings plan         50.00%
Matching contributions for all employee savings plans   $ 734 $ 549 $ 454  
First 6% of Participant Contributions          
Compensation Related Costs Disclosure [Line Items]          
Company contribution amount for each dollar a participant contributes to the savings plan 50.00%     50.00%  
Upper Limit          
Compensation Related Costs Disclosure [Line Items]          
Percentage of employee's earnings the company may contribute to the savings plan 3.00%     3.00%  
Upper Limit | IRS Compensation Limit          
Compensation Related Costs Disclosure [Line Items]          
Percentage of employee's earnings the company may contribute to the savings plan 3.00%     3.00% 50.00%
Stock Awards          
Compensation Related Costs Disclosure [Line Items]          
Shares authorized for future grant   127     127
Unrecognized compensation costs   $ 6,500     $ 6,500
Unrecognized compensation costs are expected to be recognized over a weighted average period (years)   3 years      
Weighted average grant-date fair value   $ 55.64 [1] $ 41.51 $ 42.36  
Fair value of awards vested   $ 4,800 $ 3,900 $ 4,200  
Stock Awards | Lower Limit          
Compensation Related Costs Disclosure [Line Items]          
Award vest period   4 years      
Stock Awards | Upper Limit          
Compensation Related Costs Disclosure [Line Items]          
Award vest period   5 years      
Restricted Stock Units | Executive Incentive Plan          
Compensation Related Costs Disclosure [Line Items]          
Award vest period   4 years      
Performance Stock Units | Executive Incentive Plan          
Compensation Related Costs Disclosure [Line Items]          
Award vest period   3 years      
Employee Stock          
Compensation Related Costs Disclosure [Line Items]          
Shares authorized for future grant   129     129
Percentage of market value at which employees are able to purchase shares of common stock   90.00% 90.00% 90.00%  
Maximum percentage of gross compensation at which employees may purchase shares   15.00% 15.00% 15.00% 15.00%
[1] Includes 2 million PSUs granted during fiscal year 2017. During both fiscal year 2016 and 2015 we granted 1 million PSUs.