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CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Current assets |  |  |
Cash and cash equivalents |  | $ 147 | $ 83
Accounts receivable, net |  | 860 | 797
Accrued unbilled revenues |  | 755 | 764
Inventories |  | 548 | 610
Regulatory assets |  | 464 | 424
Derivative instruments |  | 87 | 44
Prepaid taxes |  | 79 | 68
Prepayments and other |  | 154 | 183
Total current assets |  | 3,094 | 2,973
Property, plant and equipment, net |  | 36,944 | 34,329
Other assets |  |  |
Nuclear decommissioning fund and other investments |  | 2,317 | 2,397
Regulatory assets |  | 3,326 | 3,005
Derivative instruments |  | 34 | 48
Deposits and other |  | 272 | 278
Total other assets |  | 5,949 | 5,728
Total assets |  | 45,987 | 43,030
Current liabilities |  |  |
Current portion of long-term debt |  | 406 | 457
Short-term debt |  | 1,038 | 814
Accounts payable |  | 1,237 | 1,243
Regulatory liabilities | [1] | 436 | 239
Taxes accrued |  | 450 | 448
Accrued interest |  | 174 | 174
Dividends payable |  | 195 | 183
Derivative instruments |  | 61 | 29
Other |  | 463 | 501
Total current liabilities |  | 4,460 | 4,088
Deferred credits and other liabilities |  |  |
Deferred income taxes |  | 4,165 | 3,845
Deferred investment tax credits |  | 54 | 58
Regulatory liabilities | [1] | 5,187 | 5,083
Asset retirement obligations |  | 2,568 | 2,475
Derivative instruments |  | 129 | 126
Customer advances |  | 199 | 193
Pension and employee benefit obligations |  | 994 | 1,042
Other |  | 206 | 145
Total deferred credits and other liabilities |  | 13,502 | 12,967
Capitalization |  |  |
Long-term debt |  | 15,803 | 14,520
Long-term debt |  | 1,285 | 1,269
Additional paid in capital |  | 6,168 | 5,898
Retained earnings |  | 4,893 | 4,413
Accumulated other comprehensive loss |  | (124) | (125)
Common stock — 1,000,000,000 shares authorized of $2.50 par value; 514,036,787 and 507,762,881 shares outstanding at Dec. 31, 2018 and 2017, respectively |  | 12,222 | 11,455
Total liabilities and equity |  | $ 45,987 | $ 43,030
[1] | Revenue subject to refund of $29 million and $15 million for 2018 and 2017, respectively, is included in other current liabilities.

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