v3.19.3.a.u2

Debt (Corporate Revolving Facility and other Letters of Credit Facilities) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2019 | Aug. 12, 2019 | Apr. 05, 2019 | Dec. 31, 2018
Line of Credit Facility [Line Items] |  |  |  |  |  |
Debt and Lease Obligation |  |  | $ 11,706 |  |  | $ 10,785
Letters of Credit Outstanding, Amount |  |  | 1,085 |  |  | 1,365
CDHI [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Debt and Lease Obligation |  |  | $ 122 |  |  |
Applicable margin range percentage above base rate |  |  | 1.75% |  |  |
Applicable Margin Range Percentage Above British Bankers' Association Interest Settlement Rates |  |  | 2.75% |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Letters of Credit Outstanding, Amount |  |  | $ 604 |  |  | 693
Revolving Credit Facility [Member] | Amendment No. 9 [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Line of Credit Facility, Increase (Decrease), Net |  | $ 330 |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  |  | $ 2,020 |
Revolving Credit Facility [Member] | Amendment No. 8 [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  | $ 1,690 |  |  |  |
Revolving Credit Facility [Member] | Amendment No. 10 [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Line of Credit Facility, Increase (Decrease), Net | $ 20 |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  | $ 2,000 |  |
Total Letter of Credit Sub-limit |  |  |  | $ 150 |  |
Standby Letters of Credit [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Letters of Credit Outstanding, Amount |  |  | 3 |  |  | 251
Various Project Financing Facilities [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Letters of Credit Outstanding, Amount |  |  | 184 |  |  | 228
Other Corporate Facilities [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Letters of Credit Outstanding, Amount |  |  | 294 |  |  | 193
Line of Credit Facility, Maximum Borrowing Capacity |  |  | 300 |  |  |
Other Corporate Facilities [Member] | Goldman Sachs Facility 2 [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  | 100 |  |  |
Revolving Credit Facility [Member] |  |  |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |  |  |
Debt and Lease Obligation |  |  | $ 122 |  |  | $ 30

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