FAIR VALUE MEASUREMENTS, INCLUDING DERIVATIVES (Tables)

12 Months Ended

Dec. 31, 2015

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair Value, Measurement Inputs, Disclosure [Table Text Block]

	As of December 31, 2015				As of December 31, 2014
Millions of dollars	Level 1		Level 2		Level 1		Level 2
Assets:
Available for sale securities	$	11	—		$	13	—
Interest rate contracts	—		$	15	—		—
Commodity contracts	1		—		1		—
Energy management contracts	—		14		—		$	20
Liabilities:
Interest rate contracts	—		87		—		257
Commodity contracts	1		4		1		11
Energy management contracts	4		12		5		18

Fair Value, by Balance Sheet Grouping [Table Text Block]

	As of December 31, 2015				As of December 31, 2014
Millions of dollars	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Long-term debt	$	5,997.6	$	6,445.7	$	5,663.1	$	6,558.0

SCE&G

Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]

Fair Value, Measurement Inputs, Disclosure [Table Text Block]

	As of December 31, 2015		As of December 31, 2014
Millions of dollars	Level 2		Level 2
Assets-Interest rate contracts	$	15	—
Liabilities-Interest rate contracts	65		$	233

Fair Value, by Balance Sheet Grouping [Table Text Block]

	As of December 31, 2015				As of December 31, 2014
Millions of dollars	Carrying Amount		Estimated Fair Value		Carrying Amount		Estimated Fair Value
Long-term debt	$	4,769.0	$	5,129.1	$	4,279.5	$	5,041.9