Long term debt (Tables)

12 Months Ended

Dec. 31, 2015

Long-term Debt, Unclassified [Abstract]

Schedule of Long-term Debt Instruments [Table Text Block]

Long-term debt consists of the following (in millions):

	As of December 31,
	2015			2014
First Mortgage Bonds, rates range from 3.46% to 9.31%, with a weighted average rate of 5.29% in 2015 and 5.42% in 2014, due at various dates through 2048	$	2,083		$	2,075
Unsecured term bank loans, rates range from 0.86% to 0.93%, due October 2015	—			305
Pollution Control Revenue Bonds, 5% rate, due 2033	142			142
Pollution Control Revenue Bonds owned by PGE	(21		)	(21		)
Total long-term debt	2,204			2,501
Less: current portion of long-term debt	(133		)	(375		)
Long-term debt, net of current portion	$	2,071		$	2,126

Schedule of Maturities of Long-term Debt [Table Text Block]

As of December 31, 2015, the future minimum principal payments on long-term debt are as follows (in millions):

Years ending December 31:
2016	$	—
2017	58
2018	75
2019	300
2020	—
Thereafter	1,771
	$	2,204