Balance Sheet Components Other Current Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Regulatory liabilities—current	$ 49	$ 55
Accrued employee compensation and benefits	45	51
Accrued interest payable	40	25
Accrued dividends payable	29	28
Accrued taxes payable	43	25
Other	64	75
Total accrued expenses and other current liabilities	$ 270	$ 259