Debt and Credit Facilities (Annual Maturities) (Details) (USD $) In Millions, unless otherwise specified																3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Other Debt Obligations [Member]	Mar. 31, 2014 Duke Energy Carolinas [Member]	Dec. 31, 2013 Duke Energy Carolinas [Member]	Mar. 31, 2014 Progress Energy [Member]	Dec. 31, 2013 Progress Energy [Member]	Mar. 31, 2014 Duke Energy Progress [Member]	Dec. 31, 2013 Duke Energy Progress [Member]	Mar. 31, 2014 Duke Energy Florida [Member]	Dec. 31, 2013 Duke Energy Florida [Member]	Mar. 31, 2014 Duke Energy Ohio [Member]	Dec. 31, 2013 Duke Energy Ohio [Member]	Mar. 31, 2014 Duke Energy Indiana [Member]	Dec. 31, 2013 Duke Energy Indiana [Member]	Mar. 31, 2014 Parent Company [Member] 3.950% Debt Maturing September 2014 Unsecured Debt [Member]
Current Maturities Of Long Term Debt [Abstract]
Current maturities of long-term debt	$ 885	$ 2,104	$ 385	$ 47	$ 47	$ 18	$ 485	$ 6	$ 174	$ 11	$ 11	$ 599	$ 47	$ 5	$ 5	$ 500
Interest rate																3.95%
Maturity date																Sep. 30, 2014