Regulatory Matters Regulatory Matters (Decoupling and Earnings Sharing) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
OREGON | Revenue Subject to Refund [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	$ 0	$ 0
OREGON | Decoupling [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	(739)	(898)
IDAHO | Decoupling [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Assets	2,549	2,150
IDAHO | Revenue Subject to Refund [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	$ (686)	(774)
WASHINGTON
Schedule of Decoupling and Earnings Sharing [Line Items]
Decoupling Maximum Rate Increase Request	3.00%
WASHINGTON | Decoupling [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Assets	$ 22,440	12,671
WASHINGTON | Revenue Subject to Refund [Member]
Schedule of Decoupling and Earnings Sharing [Line Items]
Regulatory Liabilities	$ 0	$ (693)