Balance Sheet Components Other Current Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2017	Dec. 31, 2016
Regulatory liabilities—current	$ 42	$ 51
Accrued employee compensation and benefits	41	52
Accrued interest payable	40	25
Accrued dividends payable	30	30
Accrued taxes payable	34	25
Other	60	71
Total accrued expenses and other current liabilities	$ 247	$ 254