Commitments and Contingencies, Asset Retirement Obligations (Details) (USD $)	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	$ 424,000	[1],[2]	$ 130,000	[1]
Liabilities recognized	1,962,000		0
Accretion	17,000		7,000
Revisions to prior estimates	633,000		287,000
Ending balance	3,036,000	[1],[2]	424,000	[1],[2]
Liabilities settled	0		0
Electric Plant - Steam Production Asbestos [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	0
Liabilities recognized	1,962,000
Accretion	0
Revisions to prior estimates	0
Ending balance	1,962,000	[2]
Electric Plant - Electric Transmission and Distribution [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	357,000	[2]	67,000
Liabilities recognized	0		0
Accretion	13,000		3,000
Revisions to prior estimates	633,000		287,000
Ending balance	1,003,000	[2]	357,000	[2]
Natural Gas Plant - Gas Transmission and Distribution [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Beginning balance	67,000	[2]	63,000
Liabilities recognized	0		0
Accretion	4,000		4,000
Revisions to prior estimates	0		0
Ending balance	$ 71,000	[2]	$ 67,000	[2]

[1] Included in the other long-term liabilities balance in the consolidated balance sheets.

[2] There were no ARO liabilities settled during the 12 months ended Dec. 31, 2012 or 2011.