v3.8.0.1

Use of Collateral (Tables) | 9 Months Ended
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Sep. 30, 2017
Use of Collateral [Abstract] |
Schedule of Collateral | The table below summarizes the balances outstanding under margin deposits, natural gas and power prepayments, and exposure under letters of credit and first priority liens for commodity procurement and risk management activities as of September 30, 2017 and December 31, 2016 (in millions):
| September 30, 2017 |  | December 31, 2016
Margin deposits(1) | $ | 216 |  |  | $ | 350 |
Natural gas and power prepayments | 27 |  |  | 25 |
Total margin deposits and natural gas and power prepayments with our counterparties(2) | $ | 243 |  |  | $ | 375 |
Letters of credit issued | $ | 731 |  |  | $ | 798 |
First priority liens under power and natural gas agreements | 193 |  |  | 206 |
First priority liens under interest rate hedging instruments | 41 |  |  | 55 |
Total letters of credit and first priority liens with our counterparties | $ | 965 |  |  | $ | 1,059 |
Margin deposits posted with us by our counterparties(1)(3) | $ | 19 |  |  | $ | 16 |
Letters of credit posted with us by our counterparties | 33 |  |  | 43 |
Total margin deposits and letters of credit posted with us by our counterparties | $ | 52 |  |  | $ | 59 |
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(1) | During the third quarter of 2017, we elected to offset fair value amounts recognized for derivative instruments executed with the same counterparty under a master netting arrangement for financial statement presentation; therefore, amounts recognized for the right to reclaim, or the obligation to return, cash collateral are presented net with the corresponding derivative instrument fair values. See Note 1 for a further description of the change in accounting principle associated with our election to offset fair value amounts associated with our derivative instruments. See Note 6 for further discussion of our derivative instruments subject to master netting arrangements.
(2) | At September 30, 2017 and December 31, 2016, $85 million and $78 million, respectively, were included in current and long-term derivative assets and liabilities, $149 million and $288 million, respectively, were included in margin deposits and other prepaid expense and $9 million and $9 million, respectively, were included in other assets on our Consolidated Condensed Balance Sheets.
(3) | At September 30, 2017 and December 31, 2016, $3 million and $6 million, respectively, were included in current and long-term derivative assets and liabilities and $16 million and $10 million, respectively, were included in other current liabilities on our Consolidated Condensed Balance Sheets.

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