Consolidated Statement of Operations (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012
Pension and OPEB related adjustments to AOCI, tax	$ (9)
Net unrealized gains (losses) on cash flow hedges, tax	6
Reclassification into earnings from cash flow hedges, tax	(1)
Unrealized gain on investments in auction rate securities, tax	4
Duke Energy Carolinas [Member]
Reclassification into earnings from cash flow hedges, tax	1
Unrealized gain on investments in auction rate securities, tax	1
Progress Energy [Member]
Pension and OPEB related adjustments to AOCI, tax	(1)
Reclassification into earnings from pension and OPEB adjustments, tax	1
Net unrealized gains (losses) on cash flow hedges, tax	(3)
Reclassification into earnings from cash flow hedges, tax	6
Reclassification of cash flow hedges to regulatory assets, tax	62
Progress Energy Carolinas [Member]
Net unrealized gains (losses) on cash flow hedges, tax	(3)
Reclassification into earnings from cash flow hedges, tax	2
Reclassification of cash flow hedges to regulatory assets, tax	46
Progress Energy Florida [Member]
Net unrealized gains (losses) on cash flow hedges, tax	0
Reclassification into earnings from cash flow hedges, tax	1
Reclassification of cash flow hedges to regulatory assets, tax	16
Duke Energy Ohio [Member]
Pension and OPEB related adjustments to AOCI, tax	(8)
Reclassification into earnings from cash flow hedges, tax	0
Duke Energy Indiana [Member]
Reclassification into earnings from cash flow hedges, tax	$ (1)