Preferred Stock of Subsidiaries (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Total	$ 93	$ 0
Disclosure Preferred Stock Of Subsidiaries Details [Abstract]
Preferred stock liquidation preference per share	$ 100
Progress Energy Carolinas [Member] | Preference Stock [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Shares authorized	10,000,000	10,000,000
Progress Energy Carolinas [Member] | Cumulative Preferred Stock [Member] | Serial Preferred Stock [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Shares authorized	20,000,000	20,000,000
Progress Energy Carolinas [Member] | Cumulative Preferred Stock [Member] | Serial Preferred Stock [Member] | Preferred B [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend per share amount	$ 4.20	$ 4.20
Share outstanding	100,000	100,000
Redemption price	$ 102.00	$ 102.00
Total	10	10
Progress Energy Carolinas [Member] | Cumulative Preferred Stock [Member] | Serial Preferred Stock [Member] | Preferred C [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend per share amount	$ 5.44	$ 5.44
Share outstanding	249,850	249,850
Redemption price	$ 101.00	$ 101.00
Total	25	25
Progress Energy Carolinas [Member] | Cumulative Preferred Stock [Member] | Preferred Stock A [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Shares authorized	5,000,000	5,000,000
Progress Energy Carolinas [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member] | Preferred A [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend per share amount	$ 5.00	$ 5.00
Shares authorized	300,000	300,000
Share outstanding	236,997	236,997
Redemption price	$ 110.00	$ 110.00
Total	24	24
Progress Energy Florida [Member] | Preference Stock [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Par Value	$ 100	$ 100
Shares authorized	1,000,000	1,000,000
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Par Value	$ 100	$ 100
Shares authorized	4,000,000	4,000,000
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member] | Preferred D [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend rate percentage	4.00%	4.00%
Par Value	$ 100	$ 100
Share outstanding	39,980	39,980
Redemption price	$ 104.25	$ 104.25
Total	4	4
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member] | Preferred E [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend rate percentage	4.40%	4.40%
Par Value	$ 100	$ 100
Share outstanding	75,000	75,000
Redemption price	$ 102.00	$ 102.00
Total	8	8
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member] | Preferred F [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend rate percentage	4.58%	4.58%
Par Value	$ 100	$ 100
Share outstanding	99,990	99,990
Redemption price	$ 101.00	$ 101.00
Total	10	10
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member] | Preferred G [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend rate percentage	4.60%	4.60%
Par Value	$ 100	$ 100
Share outstanding	39,997	39,997
Redemption price	$ 103.25	$ 103.25
Total	4	4
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | Preferred Stock [Member] | Preferred H [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock dividend rate percentage	4.75%	4.75%
Par Value	$ 100	$ 100
Share outstanding	80,000	80,000
Redemption price	$ 102.00	$ 102.00
Total	$ 8	$ 8
Progress Energy Florida [Member] | Cumulative Preferred Stock [Member] | No Par Preferred Stock [Member]
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Shares authorized	5,000,000	5,000,000