XML 100 R55.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Borrowings and Other Financing Instruments Long-Term Borrowings and Other Financing Instruments (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023
Long-Term Borrowings and Other Financing Instruments |  |  |
Long-term Debt, Gross |  | $ 28,419 | $ 25,465
2025 |  | 1,103 |
2026 |  | 501 |
2027 |  | 501 |
2028 |  | 1,133 |
2029 |  | $ 503 |
NSP Minnesota |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 2.60% |
Debt Instrument, Repurchased Face Amount |  | $ 166 |
Debt Instrument, Repurchase Amount |  | 105 |
Gain (Loss) on Repurchase of Debt Instrument |  | 56 |
Xcel Energy Inc. |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Unamortized discount |  | (9) | (8)
Unamortized Debt Issuance Expense |  | (34) | (36)
Current Maturities |  | (600) | 0
Long-term Debt |  | 6,337 | 6,136
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due June 1, 2025 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.30% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due June 1, 2025 2 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.30% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Dec. 1, 2026 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.35% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due March 15, 2027 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 1.75% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due June 15, 2028 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (130) | (130)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.00% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due June 15, 2028 2 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.00% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Dec. 1, 2029 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.60% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due June 1, 2030 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (600) | (600)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.40% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Nov. 15, 2031 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.35% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due July 1, 2036 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.50% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Sept. 15, 2041 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.80% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Dec. 1, 2049 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.50% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due June 1, 2032 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (700) | (700)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.60% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Aug. 15, 2033 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [1] | $ (800) | (800)
Debt Instrument, Interest Rate, Stated Percentage | [1] | 5.45% |
Xcel Energy Inc. | Unsecured Debt [Member] | Series Due Mar. 15, 2034 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [2] | $ (800) | 0
Debt Instrument, Interest Rate, Stated Percentage | [2] | 5.50% |
NSP Minnesota |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Unamortized discount |  | $ (49) | (49)
Unamortized Debt Issuance Expense |  | (80) | (73)
Current Maturities |  | (250) | 0
Long-term Debt |  | 7,607 | 7,330
NSP Minnesota | Mortgage bonds | Series Due July 1, 2025 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 7.125% |
NSP Minnesota | Mortgage bonds | Series Due March 1, 2028 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (150) | (150)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.50% |
NSP Minnesota | Mortgage bonds | Series Due April 1, 2031 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (425) | (425)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.25% |
NSP Minnesota | Mortgage bonds | Series Due July 15, 2035 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 5.25% |
NSP Minnesota | Mortgage bonds | Series Due June 1, 2036 [Domain] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (400) | (400)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.25% |
NSP Minnesota | Mortgage bonds | Series Due July 1, 2037 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.20% |
NSP Minnesota | Mortgage bonds | Series Due Nov. 1, 2039 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 5.35% |
NSP Minnesota | Mortgage bonds | Series Due Aug. 15, 2040 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.85% |
NSP Minnesota | Mortgage bonds | Series Due Aug. 15, 2042 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.40% |
NSP Minnesota | Mortgage bonds | Series Due May 15, 2044 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.125% |
NSP Minnesota | Mortgage bonds | Series Due Aug. 15, 2045 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.00% |
NSP Minnesota | Mortgage bonds | Series Due May 15, 2046 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.60% |
NSP Minnesota | Mortgage bonds | Series Due Sept. 15, 2047 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (600) | (600)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.60% |
NSP Minnesota | Mortgage bonds | Series Due March 1, 2050 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (600) | (600)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.90% |
NSP Minnesota | Mortgage bonds | Series Due June 1, 2051 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (700) | (700)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.60% |
NSP Minnesota | Mortgage bonds | Series Due June 1, 2051 | Xcel Energy [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (166) | 0
Debt Instrument, Interest Rate, Stated Percentage |  | 2.60% |
NSP Minnesota | Mortgage bonds | Series Due April 1, 2052 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (425) | (425)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.20% |
NSP Minnesota | Mortgage bonds | Series Due June 1, 2052 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.50% |
NSP Minnesota | Mortgage bonds | Series Due May 15, 2053 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [3] | $ (800) | (800)
Debt Instrument, Interest Rate, Stated Percentage | [3] | 5.10% |
NSP Minnesota | Mortgage bonds | Series Due Mar. 15, 2054 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [4] | $ (700) | 0
Debt Instrument, Interest Rate, Stated Percentage | [4] | 5.40% |
NSP Minnesota | Long-term Debt |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (2) | (2)
NSP-Wisconsin |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Unamortized discount |  | (4) | (3)
Unamortized Debt Issuance Expense |  | (15) | (11)
Current Maturities |  | 0 | (200)
Long-term Debt |  | 1,406 | 1,011
NSP-Wisconsin | Mortgage bonds | Series Due Sept. 1, 2038 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (200) | (200)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.375% |
NSP-Wisconsin | Mortgage bonds | Series Due Oct. 1, 2042 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.70% |
NSP-Wisconsin | Mortgage bonds | Series Due Dec. 1, 2047 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.75% |
NSP-Wisconsin | Mortgage bonds | Series Due September 1, 2048 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (200) | (200)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.20% |
NSP-Wisconsin | Mortgage bonds | Series Due May 1, 2051 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.05% |
NSP-Wisconsin | Mortgage bonds | Series Due May 1, 2051 2 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.82% |
NSP-Wisconsin | Mortgage bonds | Series Due June 15, 2024 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ 0 | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.30% |
NSP-Wisconsin | Mortgage bonds | Series Due June 15, 2024 2 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ 0 | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.30% |
NSP-Wisconsin | Mortgage bonds | Series Due Sept. 15, 2052 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.86% |
NSP-Wisconsin | Mortgage bonds | Series Due June 15, 2053 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [5] | $ (125) | (125)
Debt Instrument, Interest Rate, Stated Percentage | [5] | 5.30% |
NSP-Wisconsin | Mortgage bonds | Series Due June 15, 2054 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [6] | $ (400) | 0
Debt Instrument, Interest Rate, Stated Percentage | [6] | 5.65% |
PSCo |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Unamortized discount |  | $ (42) | (41)
Unamortized Debt Issuance Expense |  | (67) | (59)
Current Maturities |  | (250) | 0
Long-term Debt |  | 8,391 | 7,450
PSCo | Mortgage bonds | Series Due June 15, 2028 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.70% |
PSCo | Mortgage bonds | Series Due March 1, 2050 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (550) | (550)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.20% |
PSCo | Mortgage bonds | Series Due May 15, 2025 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.90% |
PSCo | Mortgage bonds | Series Due Jan. 15, 2031 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (375) | (375)
Debt Instrument, Interest Rate, Stated Percentage |  | 1.90% |
PSCo | Mortgage bonds | Series Due June 15, 2031 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (750) | (750)
Debt Instrument, Interest Rate, Stated Percentage |  | 1.875% |
PSCo | Mortgage bonds | Series Due Sept. 1, 2037 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.25% |
PSCo | Mortgage bonds | Series Due Aug. 1, 2038 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.50% |
PSCo | Mortgage bonds | Series Due Aug. 15, 2041 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.75% |
PSCo | Mortgage bonds | Series Due Sept. 15, 2042 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (500) | (500)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.60% |
PSCo | Mortgage bonds | Series Due March 15, 2043 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.95% |
PSCo | Mortgage bonds | Series Due March 15, 2044 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.30% |
PSCo | Mortgage bonds | Series Due June 15, 2046 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.55% |
PSCo | Mortgage bonds | Series Due June 15, 2047 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (400) | (400)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.80% |
PSCo | Mortgage bonds | Series Due June 15, 2048 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.10% |
PSCo | Mortgage bonds | Series Due September 15, 2049 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (400) | (400)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.05% |
PSCo | Mortgage bonds | Series Due Jan. 15, 2051 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (375) | (375)
Debt Instrument, Interest Rate, Stated Percentage |  | 2.70% |
PSCo | Mortgage bonds | Series Due June 1, 2052 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (400) | (400)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.50% |
PSCo | Mortgage bonds | Series Due June 1, 2032 2 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.10% |
PSCo | Mortgage bonds | Series Due April 1, 2053 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [7] | $ (850) | (850)
Debt Instrument, Interest Rate, Stated Percentage | [7] | 5.25% |
PSCo | Mortgage bonds | Series Due May 15, 2034 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [8] | $ (450) | 0
Debt Instrument, Interest Rate, Stated Percentage | [8] | 5.35% |
PSCo | Mortgage bonds | Series Due May 15, 2054 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [8] | $ (750) | 0
Debt Instrument, Interest Rate, Stated Percentage | [8] | 5.75% |
SPS |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Unamortized discount |  | $ (14) | (10)
Unamortized Debt Issuance Expense |  | (35) | (29)
Current Maturities |  | 0 | (350)
Long-term Debt |  | 3,551 | 2,961
SPS | Mortgage bonds | Series Due June 15, 2024 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ 0 | (150)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.30% |
SPS | Mortgage bonds | Series Due June 15, 2024 2 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ 0 | (200)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.30% |
SPS | Mortgage bonds | Series Due Aug. 15, 2041 4 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (200) | (200)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.50% |
SPS | Mortgage bonds | Series Due Aug. 15, 2041 2 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.50% |
SPS | Mortgage bonds | Series Due Aug. 15, 2041 3 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.50% |
SPS | Mortgage bonds | Series Due August 15, 2046 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.40% |
SPS | Mortgage bonds | Series Due August 15, 2047 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (450) | (450)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.70% |
SPS | Mortgage bonds | Series Due Nov. 15, 2048 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 4.40% |
SPS | Mortgage bonds | Series Due June 15, 2049 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (300) | (300)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.75% |
SPS | Mortgage bonds | Series due May 1, 2050 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (350) | (350)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.15% |
SPS | Mortgage bonds | Series due May 1, 2050 2 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 3.15% |
SPS | Mortgage bonds | Series Due June 1, 2052 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (200) | (200)
Debt Instrument, Interest Rate, Stated Percentage |  | 5.15% |
SPS | Mortgage bonds | Series Due Sept. 15, 2053 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [9] | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage | [9] | 6.00% |
SPS | Mortgage bonds | Series Due June 15, 2054 |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount | [10] | $ (600) | 0
Debt Instrument, Interest Rate, Stated Percentage | [10] | 6.00% |
SPS | Unsecured Debt [Member] | Senior C and D Due Oct. 1, 2033 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (100) | (100)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.00% |
SPS | Unsecured Debt [Member] | Senior F Due Oct. 1, 2036 [Member] |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Face Amount |  | $ (250) | (250)
Debt Instrument, Interest Rate, Stated Percentage |  | 6.00% |
Other Subsidiaries |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Current Maturities |  | $ (3) | (2)
Long-term Debt |  | 24 | 25
Other Subsidiaries | Various Eloigne Co. affordable housing project notes |  |  |
Long-Term Borrowings and Other Financing Instruments |  |  |
Long-term Debt, Gross |  | $ 27 | $ 27
[1] | 2023 financing
[2] | 2024 financing
[3] | 2023 financing.
[4] | 2024 financing.
[5] | 2023 financing.
[6] | 2024 financing.
[7] | 2023 financing.
[8] | 2024 financing
[9] | 2023 financing.
[10] | 2024 financing

X
- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-4 + Details
Name: | us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482949/835-30-55-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69B -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69C -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482900/835-30-50-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482925/835-30-45-2 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482949/835-30-55-8 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(f)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69B -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69C -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C Reference 7: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69E -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69E Reference 8: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69F -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69F Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 11: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1F -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1F -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1F -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1F -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1F Reference 25: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1I -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1I Reference 26: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482925/835-30-45-2 Reference 27: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482900/835-30-50-1 + Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value amount of debt instrument that was repurchased. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentRepurchaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Face (par) amount of the original debt instrument that was repurchased. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentRepurchasedFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after accumulated amortization, of debt discount (premium). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482925/835-30-45-1A Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482925/835-30-45-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482900/835-30-50-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D + Details
Name: | us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of gain (loss) from the difference between the repurchase price of a debt instrument initially issued by the entity and the net carrying amount of the debt at the time of its repurchase. + References No definition available. + Details
Name: | us-gaap_GainLossOnRepurchaseOfDebtInstrument
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482949/835-30-55-8 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69B -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69C -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-4 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(20)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_LongTermDebtCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 470 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481544/470-10-50-1 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 470 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481544/470-10-50-1 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 470 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481544/470-10-50-1 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 470 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481544/470-10-50-1 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1E -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1E Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 470 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481544/470-10-50-1 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. + References No definition available. + Details
Name: | us-gaap_UnamortizedDebtIssuanceExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=xel_NspMinnesotaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=xel_XCELENERGYINCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune12025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune120252Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueDec.12026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMarch152027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152028Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune1520282Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueDec.12029Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune12030Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueNov152031Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJuly12036Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept.152041Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueDec.12049Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune12032Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.152033Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMar.152034Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=xel_NspMinnesotaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_BondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJuly12025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMarch12028Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueApril12031Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJuly152035Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune12036Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJuly12037Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueNov.12039Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.152040Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.152042Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay152044Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.152045Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay152046Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept.152047Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMarch12050Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune12051Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=xel_XcelEnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueApril12052Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune12052Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay152053Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMar.152054Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_LongTermDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=xel_NSPWisconsinMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept.12038Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueOct.12042Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueDecember12047Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSeptember12048Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay12051Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay120512Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune1520242Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept152052Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152053Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152054Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=xel_PscoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay152025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJan152031Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152031Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept.12037Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.12038Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug152041Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept.152042Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMarch152043Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMarch152044Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152046Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152047Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152048Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSeptember152049Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJan152051Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune120322Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueApril12053Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay152034Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay152054Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=xel_SpsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug1520414Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.1520412Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAug.1520413Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAugust152046Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueAugust152047Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueNov.152048Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueJune152049Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay12050Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueMay120502Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeriesDueSept.152053Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeniorCAndDDueOct12033Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=xel_SeniorFDueOct12036Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=xel_OtherSubsidiariesDomain
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=xel_VariousEloigneCoAffordableHousingProjectNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |