Severance Expense Table (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013		Jun. 30, 2013
Restructuring Cost and Reserve [Line Items]
Severance expense	$ 9	[1]	$ 25	[1]
Accelerated stock compensation expense			5
Duke Energy Carolinas [Member]
Restructuring Cost and Reserve [Line Items]
Severance expense	2		7
Progress Energy [Member]
Restructuring Cost and Reserve [Line Items]
Severance expense	6		13
Duke Energy Progress [Member]
Restructuring Cost and Reserve [Line Items]
Severance expense	4		9
Duke Energy Florida [Member]
Restructuring Cost and Reserve [Line Items]
Severance expense	2		4
Duke Energy Ohio [Member]
Restructuring Cost and Reserve [Line Items]
Severance expense	1		2
Duke Energy Indiana [Member]
Restructuring Cost and Reserve [Line Items]
Severance expense	$ 1		$ 2

[1] Includes $5 million of accelerated stock award expense for the six months ended June 30, 2013. There was an insignificant amount of accelerated stock award expense for the three months ended June 30, 2013.