v3.3.0.814

Investments in Debt and Equity Securities (Maturities) (Details) $ in Millions | Sep. 30, 2015 USD ($)
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Debt Instrument [Line Items] |
Due in one year or less | $ 74
Due after one through five years | 781
Due after five through 10 years | 635
Due after 10 years | 812
Total | 2,302
Duke Energy Carolinas [Member] |
Debt Instrument [Line Items] |
Due in one year or less | 13
Due after one through five years | 209
Due after five through 10 years | 293
Due after 10 years | 423
Total | 938
Progress Energy [Member] |
Debt Instrument [Line Items] |
Due in one year or less | 38
Due after one through five years | 476
Due after five through 10 years | 271
Due after 10 years | 333
Total | 1,118
Duke Energy Progress [Member] |
Debt Instrument [Line Items] |
Due in one year or less | 12
Due after one through five years | 278
Due after five through 10 years | 219
Due after 10 years | 240
Total | 749
Duke Energy Florida [Member] |
Debt Instrument [Line Items] |
Due in one year or less | 26
Due after one through five years | 198
Due after five through 10 years | 52
Due after 10 years | 93
Total | 369
Duke Energy Indiana [Member] |
Debt Instrument [Line Items] |
Due in one year or less | 2
Due after one through five years | 16
Due after five through 10 years | 8
Due after 10 years | 4
Total | $ 30

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- Definition Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563 + Details
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- Definition Fair value of available-for-sale debt securities maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563 + Details
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- Definition Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62586-112803 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 + Details
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