Rate Matters (Details)	3 Months Ended
Mar. 31, 2017
CPUC Proceeding - Annual Electric Earnings Test
Rate Matters [Abstract]
Public Utilities, Return On Equity Threshold For Earnings Sharing For 2015 Through 2017	9.83%

The return on equity used as a threshold in the public utility's annual earnings test for 2012-2014, as approved by a regulatory agency. Earnings exceeding this threshold are shared between customers and shareholders.

No definition available.

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Period Type:	duration