Derivative Instruments (Credit-Risk-Related Contingent Features) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Fair value of derivative instruments with credit-risk-related contingent features that were in a liability position	$ 2,500,000,000	$ 2,700,000,000
Total required posted collateral should FPL's and Capital Holdings' credit ratings fall to BBB/Baa2	500,000,000	700,000,000
Total required posted collateral should FLP's and Capital Holdings' credit ratings fall below investment grade	2,600,000,000	2,800,000,000
Additional collateral requirements if non-ratings based contract provisions are triggered	750,000,000	850,000,000
Collateral Already Posted	118,000,000
Letters of credit posted through the normal course of business that could be applied toward the collateral requirements related to derivative instruments with credit-risk-related contingent features	117,000,000	236,000,000
FPL [Member]
Derivative [Line Items]
Fair value of derivative instruments with credit-risk-related contingent features that were in a liability position	375,000,000	369,000,000
Total required posted collateral should FPL's and Capital Holdings' credit ratings fall to BBB/Baa2	130,000,000	130,000,000
Total required posted collateral should FLP's and Capital Holdings' credit ratings fall below investment grade	700,000,000	700,000,000
Additional collateral requirements if non-ratings based contract provisions are triggered	175,000,000	200,000,000
Collateral Already Posted	0
Letters of credit posted through the normal course of business that could be applied toward the collateral requirements related to derivative instruments with credit-risk-related contingent features	$ 0	$ 0