Income Taxes (Deferred Income Taxes) (Details) - USD ($) $ in Millions |
3 Months Ended |
12 Months Ended |
Mar. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
$ 245
|
$ 188
|
|
Capital lease obligations |
|
63
|
63
|
|
Pension, postretirement and other employee benefits |
|
580
|
546
|
|
Progress Energy merger purchase accounting adjustments |
|
1,009
|
1,124
|
|
Tax credits and NOL carryforwards |
|
3,719
|
3,540
|
|
Other |
|
206
|
|
|
Valuation allowance |
|
(160)
|
(184)
|
|
Total deferred income tax assets |
|
5,662
|
5,277
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Investments and other assets |
|
(1,584)
|
(1,625)
|
|
Accelerated depreciation rates |
|
(13,070)
|
(11,715)
|
|
Regulatory assets and deferred debits, net |
|
(3,633)
|
(3,694)
|
|
Other |
|
|
(44)
|
|
Total deferred income tax liabilities |
|
(18,287)
|
(17,078)
|
|
Net deferred income tax liabilities |
|
(12,625)
|
(11,801)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
3,719
|
3,540
|
|
Valuation allowance |
|
(160)
|
(184)
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
1,593
|
|
Investments and Other Assets: Other |
|
80
|
29
|
|
Deferred Credits and Other Liabilities: Other |
|
(12,705)
|
(13,423)
|
|
Net deferred income tax liabilities |
|
(12,625)
|
(11,801)
|
|
State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Net reduction in deferred tax liability |
|
95
|
|
$ 145
|
Investment Tax Credits [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
864
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 864
|
|
|
Investment Tax Credits [Member] | Minimum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2029
|
|
|
Investment Tax Credits [Member] | Maximum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2035
|
|
|
Alternative Minimum Tax Credit [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 1,121
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
1,121
|
|
|
NOL Carryforwards [Member] | Federal [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
484
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 484
|
|
|
NOL Carryforwards [Member] | Federal [Member] | Minimum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2030
|
|
|
NOL Carryforwards [Member] | Federal [Member] | Maximum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2033
|
|
|
NOL Carryforwards [Member] | State [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 299
|
|
|
Valuation allowance |
|
(81)
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
299
|
|
|
Valuation allowance |
|
$ (81)
|
|
|
NOL Carryforwards [Member] | State [Member] | Minimum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2016
|
|
|
NOL Carryforwards [Member] | State [Member] | Maximum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2035
|
|
|
NOL Carryforwards [Member] | Foreign Jurisdictions [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 100
|
|
|
Valuation allowance |
|
(79)
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
100
|
|
|
Valuation allowance |
|
$ (79)
|
|
|
NOL Carryforwards [Member] | Foreign Jurisdictions [Member] | Minimum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2026
|
|
|
NOL Carryforwards [Member] | Foreign Jurisdictions [Member] | Maximum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2034
|
|
|
Foreign Tax Credit [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 851
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
$ 851
|
|
|
Foreign Tax Credit [Member] | Foreign Jurisdictions [Member] | Minimum [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Expiration year |
|
Dec. 31, 2024
|
|
|
Duke Energy Carolinas [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
$ 38
|
53
|
|
Capital lease obligations |
|
9
|
10
|
|
Pension, postretirement and other employee benefits |
|
46
|
4
|
|
Tax credits and NOL carryforwards |
|
170
|
157
|
|
Other |
|
20
|
12
|
|
Total deferred income tax assets |
|
283
|
236
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Investments and other assets |
|
(1,057)
|
(1,051)
|
|
Accelerated depreciation rates |
|
(4,429)
|
(4,046)
|
|
Regulatory assets and deferred debits, net |
|
(943)
|
(953)
|
|
Total deferred income tax liabilities |
|
(6,429)
|
(6,050)
|
|
Net deferred income tax liabilities |
|
(6,146)
|
(5,814)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
170
|
157
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
3
|
|
Current Liabilities: Other |
|
|
(5)
|
|
Deferred Credits and Other Liabilities: Other |
|
(6,146)
|
(5,812)
|
|
Net deferred income tax liabilities |
|
(6,146)
|
(5,814)
|
|
Progress Energy [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
115
|
108
|
|
Pension, postretirement and other employee benefits |
|
186
|
188
|
|
Tax credits and NOL carryforwards |
|
997
|
980
|
|
Other |
|
48
|
|
|
Valuation allowance |
|
(38)
|
(13)
|
|
Total deferred income tax assets |
|
1,308
|
1,263
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Investments and other assets |
|
(412)
|
(427)
|
|
Accelerated depreciation rates |
|
(4,169)
|
(3,284)
|
|
Regulatory assets and deferred debits, net |
|
(1,517)
|
(1,602)
|
|
Other |
|
|
(151)
|
|
Total deferred income tax liabilities |
|
(6,098)
|
(5,464)
|
|
Net deferred income tax liabilities |
|
(4,790)
|
(4,201)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
997
|
980
|
|
Valuation allowance |
|
(38)
|
(13)
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
558
|
|
Deferred Credits and Other Liabilities: Other |
|
(4,790)
|
(4,759)
|
|
Net deferred income tax liabilities |
|
(4,790)
|
(4,201)
|
|
Duke Energy Progress [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
25
|
28
|
|
Pension, postretirement and other employee benefits |
|
92
|
96
|
|
Tax credits and NOL carryforwards |
|
163
|
91
|
|
Other |
|
2
|
55
|
|
Valuation allowance |
|
|
(1)
|
|
Total deferred income tax assets |
|
282
|
269
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Investments and other assets |
|
(228)
|
(232)
|
|
Accelerated depreciation rates |
|
(2,325)
|
(2,030)
|
|
Regulatory assets and deferred debits, net |
|
(756)
|
(809)
|
|
Total deferred income tax liabilities |
|
(3,309)
|
(3,071)
|
|
Net deferred income tax liabilities |
|
(3,027)
|
(2,802)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
163
|
91
|
|
Valuation allowance |
|
|
(1)
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
106
|
|
Deferred Credits and Other Liabilities: Other |
|
(3,027)
|
(2,908)
|
|
Net deferred income tax liabilities |
|
(3,027)
|
(2,802)
|
|
Duke Energy Florida [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
66
|
78
|
|
Pension, postretirement and other employee benefits |
|
82
|
93
|
|
Tax credits and NOL carryforwards |
|
177
|
252
|
|
Other |
|
46
|
|
|
Total deferred income tax assets |
|
371
|
423
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Investments and other assets |
|
(201)
|
(245)
|
|
Accelerated depreciation rates |
|
(1,868)
|
(1,252)
|
|
Regulatory assets and deferred debits, net |
|
(762)
|
(792)
|
|
Other |
|
|
(246)
|
|
Total deferred income tax liabilities |
|
(2,831)
|
(2,535)
|
|
Net deferred income tax liabilities |
|
(2,460)
|
(2,112)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
177
|
252
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
340
|
|
Deferred Credits and Other Liabilities: Other |
|
(2,460)
|
(2,452)
|
|
Net deferred income tax liabilities |
|
(2,460)
|
(2,112)
|
|
Duke Energy Ohio [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
29
|
(8)
|
|
Pension, postretirement and other employee benefits |
|
24
|
17
|
|
Tax credits and NOL carryforwards |
|
25
|
38
|
|
Investments and other assets |
|
3
|
14
|
|
Other |
|
37
|
35
|
|
Total deferred income tax assets |
|
118
|
96
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Accelerated depreciation rates |
|
(1,356)
|
(1,660)
|
|
Regulatory assets and deferred debits, net |
|
(169)
|
(141)
|
|
Total deferred income tax liabilities |
|
(1,525)
|
(1,801)
|
|
Net deferred income tax liabilities |
|
(1,407)
|
(1,705)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
25
|
38
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
60
|
|
Deferred Credits and Other Liabilities: Other |
|
(1,407)
|
(1,765)
|
|
Net deferred income tax liabilities |
|
(1,407)
|
(1,705)
|
|
Duke Energy Indiana [Member] |
|
|
|
|
Deferred Tax Assets, Gross [Abstract] |
|
|
|
|
Deferred credits and other liabilities |
|
5
|
12
|
|
Capital lease obligations |
|
2
|
2
|
|
Pension, postretirement and other employee benefits |
|
40
|
43
|
|
Tax credits and NOL carryforwards |
|
215
|
260
|
|
Other |
|
20
|
11
|
|
Total deferred income tax assets |
|
282
|
328
|
|
Deferred Tax Liabilities, Gross [Abstract] |
|
|
|
|
Investments and other assets |
|
(7)
|
(4)
|
|
Accelerated depreciation rates |
|
(1,797)
|
(1,603)
|
|
Regulatory assets and deferred debits, net |
|
(135)
|
(106)
|
|
Total deferred income tax liabilities |
|
(1,939)
|
(1,713)
|
|
Net deferred income tax liabilities |
|
(1,657)
|
(1,385)
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Tax credits and NOL carryforwards |
|
215
|
260
|
|
Classification of Deferred Tax Assets (Liabiliities) in the Consolidated Balance Sheets [Abstract] |
|
|
|
|
Current Assets: Other |
|
|
206
|
|
Deferred Credits and Other Liabilities: Other |
|
(1,657)
|
(1,591)
|
|
Net deferred income tax liabilities |
|
$ (1,657)
|
$ (1,385)
|
|
2013 [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
|
|
6.90%
|
2013 [Member] | Duke Energy Carolinas [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
|
|
6.90%
|
2013 [Member] | Duke Energy Progress [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
|
|
6.90%
|
January 2014 [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
|
6.00%
|
|
January 2014 [Member] | Duke Energy Carolinas [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
|
6.00%
|
|
January 2014 [Member] | Duke Energy Progress [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
|
6.00%
|
|
January 2015 [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
5.00%
|
|
|
January 2015 [Member] | Duke Energy Carolinas [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
5.00%
|
|
|
January 2015 [Member] | Duke Energy Progress [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
|
5.00%
|
|
|
Scenario, Forecast [Member] | January 2016 [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
4.00%
|
|
|
|
Scenario, Forecast [Member] | January 2016 [Member] | Duke Energy Carolinas [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
4.00%
|
|
|
|
Scenario, Forecast [Member] | January 2016 [Member] | Duke Energy Progress [Member] | State [Member] |
|
|
|
|
Components and Expiration Dates of Tax Credits and NOL Carryforwards [Abstract] |
|
|
|
|
Statutory Tax Rate |
4.00%
|
|
|
|