Commitments And Contingencies (Details) (USD $)	1 Months Ended		9 Months Ended
	Mar. 31, 2007 family	May 31, 2004	Sep. 30, 2013 hydroelectric_plant	Mar. 30, 2007
Amount of Regulatory Costs Not yet Approved			$ 1,300,000
Investigation review bid maximum (per MW)		250
Customer refund liability			200,000
Number of families that own property near the holding ponds who filed a complaint	2
Owners percentage interest				15.00%
Number of hydroelectric plants			6
Number of years, license issued			50 years
WASHINGTON
Amount of Regulatory Costs Not yet Approved			900,000
IDAHO
Amount of Regulatory Costs Not yet Approved			$ 400,000