Segment Reporting, Disclosure of Major Customers

For the three months ended June 30, 2017, no single customer represented more than 10% of the Gas, or Water operating segment revenues.

For the three months ended June 30, 2016, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.

For the six months ended June 30, 2017, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.

For the six months ended June 30, 2016, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.

Revenue, Major Customer [Line Items]

Concentration Risk, Percentage

11.00%

Revenue, Major Customer [Line Items]

Concentration Risk, Percentage

12.00%

13.00%

Segment Information Major Customers (Details)	3 Months Ended		6 Months Ended
Segment Information Major Customers (Details)	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue, Major Customer [Line Items]
Segment Reporting, Disclosure of Major Customers	For the three months ended June 30, 2017, no single customer represented more than 10% of the Gas, or Water operating segment revenues.	For the three months ended June 30, 2016, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.	For the six months ended June 30, 2017, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.	For the six months ended June 30, 2016, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.
Revenue [Member] \| Threshold for Reporting Customer Concentration [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	10.00%	10.00%	10.00%	10.00%
Revenue [Member] \| Customer A [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	11.00%
Revenue [Member] \| Customer A [Member] \| Electricity Operating Segment [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	22.00%		20.00%
Revenue [Member] \| Customer B [Member] \| Electricity Operating Segment [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage		12.00%		13.00%