Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Allowance for doubtful accounts	$ 66	$ 80
Common stock, shares authorized	800,000,000	800,000,000
Common stock, shares outstanding	475,913,404	456,670,424
Pacific Gas And Electric Company [Member]
Allowance for doubtful accounts	$ 66	$ 80
Common stock, par value	$ 5	$ 5
Common stock, shares authorized	800,000,000	800,000,000
Common stock, shares outstanding	264,374,809	264,374,809