Segment Reporting, Disclosure of Major Customers

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

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

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

For the nine months ended September 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

10.00%

Revenue, Major Customer [Line Items]

Concentration Risk, Percentage

14.00%

10.00%

Revenue, Major Customer [Line Items]

Segment Information Major Customers (Details)	3 Months Ended		9 Months Ended
Segment Information Major Customers (Details)	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue, Major Customer [Line Items]
Segment Reporting, Disclosure of Major Customers	For the three months ended September 30, 2017, no single customer represented more than 10% of the Gas, or Water operating segment revenues.	For the three months ended September 30, 2016, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.	For the nine months ended September 30, 2017, no single customer represented more than 10% of total Company, or the Gas, or Water operating segment revenues.	For the nine months ended September 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	10.00%
Revenue [Member] \| Customer A [Member] \| Electricity Operating Segment [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	20.00%	14.00%	20.00%
Revenue [Member] \| Customer B [Member] \| Electricity Operating Segment [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage	14.00%		10.00%
Revenue [Member] \| Customer C [Member] \| Electricity Operating Segment [Member]
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage				12.00%