v3.19.3

Derivative Financial Instruments (Narrative) (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2019 USD ($) bbl | Mar. 31, 2019 USD ($) | Sep. 30, 2019 USD ($) bbl | Sep. 30, 2018 USD ($) | Dec. 31, 2018 USD ($)
Derivative [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 4,750,000,000 |  | $ 4,750,000,000 |  | $ 4,300,000,000
Net receipt (payment) on financial derivatives |  |  | (33,342,000) | $ 20,925,000 |
Good Faith and Margin Deposits with Broker-Dealers | 21,811,000 |  | 21,811,000 |  | 0
Energy commodity derivatives deposits | 0 |  | 0 |  | 37,328,000
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months | $ (3,200,000) |  | $ (3,200,000) |  |
Energy Related Derivative [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Derivative, Nonmonetary Notional Amount | bbl | 30,000 |  | 30,000 |  |
Derivative Liability | $ 17,800,000 |  | $ 17,800,000 |  |
Three Point Nine Five Percentage Notes Due Two Thousand Fifty [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 500,000,000.0 |  | $ 500,000,000.0 |  | 0
Debt Instrument, Interest Rate, Stated Percentage | 3.95% |  | 3.95% |  |
Three Point Nine Five Percentage Notes Due Two Thousand Fifty [Member] | Cash Flow Hedging [Member] | Interest Rate Contract [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Net receipt (payment) on financial derivatives | $ (25,300,000) |  |  |  |
4.85% Notes Due 2049 [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Debt Instrument, Face Amount | $ 500,000,000 | $ 500,000,000.0 | $ 500,000,000 |  | $ 0
Debt Instrument, Interest Rate, Stated Percentage | 4.85% | 4.85% | 4.85% |  |
4.85% Notes Due 2049 [Member] | Cash Flow Hedging [Member] | Interest Rate Contract [Member] |  |  |  |  |
Derivative [Line Items] |  |  |  |  |
Net receipt (payment) on financial derivatives |  | $ (8,000,000.0) |  |  |

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