Employee Benefit Plans (Reconciliation of Assets Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 13	$ 85	$ 146
Purchases	30	36	16
Sales	(6)	(2)	(3)
Transfers in and/or out of level 3	86
Total pretax gains (losses) included in earnings	42	(8)	14
Ending balance	111	13	85
Master Trust [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	352	322
Combination of trust assets	288
Purchases	25	21
Sales	(152)	(4)
Total pretax gains (losses) included in earnings	33	13
Ending balance	546	352
Progress Energy [Member] | Master Trust [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	288	311
Combination of trust assets	(288)
Purchases	0	13
Sales	0	(14)
Transfers in and/or out of level 3	0	(41)
Total pretax gains (losses) included in earnings	0	19
Ending balance	$ 0	$ 288