v3.20.2

Basis of Presentation and Summary of Significant Accounting Policies - Components of Restricted Cash (Details) - USD ($) $ in Millions | Sep. 30, 2020 | Jun. 30, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Accounting Policies [Line Items] |  |  |
Current |  | $ 225 | $ 299
Non-current |  | 16 | 46
Total |  | 241 | 345
Debt service |  |  |
Accounting Policies [Line Items] |  |  |
Current |  | 55 | 58
Non-current |  | 8 | 8
Total |  | 63 | 66
Construction major maintenance |  |  |
Accounting Policies [Line Items] |  |  |
Current |  | 35 | 28
Non-current |  | 7 | 6
Total |  | 42 | 34
Margin Deposits Received/Returned to PG&E [Member] |  |  |
Accounting Policies [Line Items] |  |  |
Total |  | 119 |
Security project insurance |  |  |
Accounting Policies [Line Items] |  |  |
Current |  | 130 | 209
Non-current |  | 0 | 31
Total |  | 130 | 240
Other |  |  |
Accounting Policies [Line Items] |  |  |
Current |  | 5 | 4
Non-current |  | 1 | 1
Total |  | $ 6 | $ 5
Subsequent Event | Debt service |  |  |
Accounting Policies [Line Items] |  |  |
Total | $ 52 |  |
Subsequent Event | Construction major maintenance |  |  |
Accounting Policies [Line Items] |  |  |
Total | 2 |  |
Subsequent Event | Security project insurance |  |  |
Accounting Policies [Line Items] |  |  |
Total | $ 34 |  |

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- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3044-108585 + Details
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