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Schedule I, Condensed Financial Statements of Xcel Energy Inc, Condensed Statements of Income (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Income |  |  |  |  |  |  |  |  |  |  |
Income (Loss) from Equity Method Investments |  |  |  |  |  |  |  |  | $ 35 | $ 30 | $ 42
Expenses and other deductions |  |  |  |  |  |  |  |  |  |  |
Other income |  |  |  |  |  |  |  |  | 14 | 10 | 18
Interest charges and financing costs |  |  |  |  |  |  |  |  | 700 | 663 | 647
Income before income taxes |  |  |  |  |  |  |  |  | 1,442 | 1,690 | 1,704
Income tax benefit |  |  |  |  |  |  |  |  | 181 | 542 | 581
Net income | $ 214 | $ 491 | $ 265 | $ 291 | $ 189 | $ 492 | $ 227 | $ 239 | 1,261 | 1,148 | 1,123
Other Comprehensive Income (Loss), Net of Tax [Abstract] |  |  |  |  |  |  |  |  |  |  |
Pension and retiree medical benefits, net of tax of $1, $3 and $(3) respectively |  |  |  |  |  |  |  |  | (6) | (3) | (8)
Other Comprehensive Income (Loss), Net of Tax |  |  |  |  |  |  |  |  | 1 | 7 |
Comprehensive Income, Net of Tax |  |  |  |  |  |  |  |  | $ 1,262 | $ 1,155 | $ 1,123
Weighted average common shares outstanding: |  |  |  |  |  |  |  |  |  |  |
Basic (in shares) |  |  |  |  |  |  |  |  | 511 | 509 | 509
Diluted (in shares) |  |  |  |  |  |  |  |  | 511 | 509 | 509
Earnings per average common share: |  |  |  |  |  |  |  |  |  |  |
Basic (in dollars per share) | $ 0.42 | $ 0.96 | $ 0.52 | $ 0.57 | $ 0.37 | $ 0.97 | $ 0.45 | $ 0.47 | $ 2.47 | $ 2.26 | $ 2.21
Diluted (in dollars per share) | 0.42 | 0.96 | 0.52 | 0.57 | 0.37 | 0.97 | 0.45 | 0.47 | 2.47 | 2.25 | 2.21
Cash dividends declared per common share (in dollars per share) | $ 0.38 | $ 0.38 | $ 0.38 | $ 0.38 | $ 0.36 | $ 0.36 | $ 0.36 | $ 0.36 | $ 1.52 | $ 1.44 | $ 1.36
Xcel Energy Inc. |  |  |  |  |  |  |  |  |  |  |
Income |  |  |  |  |  |  |  |  |  |  |
Income (Loss) from Equity Method Investments |  |  |  |  |  |  |  |  | $ 1,393 | $ 1,263 | $ 1,199
Total income |  |  |  |  |  |  |  |  | 1,393 | 1,263 | 1,199
Expenses and other deductions |  |  |  |  |  |  |  |  |  |  |
Operating expenses |  |  |  |  |  |  |  |  | 24 | 30 | 22
Other income |  |  |  |  |  |  |  |  | (1) | (6) | (3)
Interest charges and financing costs |  |  |  |  |  |  |  |  | 149 | 128 | 116
Total expenses and other deductions |  |  |  |  |  |  |  |  | 172 | 152 | 135
Income before income taxes |  |  |  |  |  |  |  |  | 1,221 | 1,111 | 1,064
Income tax benefit |  |  |  |  |  |  |  |  | (40) | (37) | (59)
Net income |  |  |  |  |  |  |  |  | 1,261 | 1,148 | 1,123
Other Comprehensive Income (Loss), Net of Tax [Abstract] |  |  |  |  |  |  |  |  |  |  |
Pension and retiree medical benefits, net of tax of $1, $3 and $(3) respectively |  |  |  |  |  |  |  |  | 3 | 4 | (4)
Derivative instruments, net of tax of $(1), $2 and $2, respectively |  |  |  |  |  |  |  |  | (2) | 3 | 4
Other Comprehensive Income (Loss), Net of Tax |  |  |  |  |  |  |  |  | 1 | 7 | 0
Comprehensive Income, Net of Tax |  |  |  |  |  |  |  |  | $ 1,262 | $ 1,155 | $ 1,123

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