Supplemental Balance Sheet Information (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2013
Other current assets
Total other current assets	$ 1,521	$ 1,298
Investments
Total investments	106	102
Other assets
Total other assets	1,055	1,554
Other current liabilities
Dividends payable		600	$ 600
Total other current liabilities	2,386	2,918
Other liabilities
Total other liabilities	$ 1,049	$ 1,555