v2.4.0.6

Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2012
Summary of Significant Accounting Policies [Abstract] |
Schedule of Jointly Owned Utility Plants [Table Text Block] | Jointly-Owned Plants — Certain of our subsidiaries own undivided interests in jointly-owned plants. These plants are maintained and operated pursuant to their joint ownership participation and operating agreements. We are responsible for our subsidiaries’ share of operating costs and direct expenses and include our proportionate share of the facilities and related revenues and direct expenses in these jointly-owned plants in the corresponding balance sheet and income statement captions of our Consolidated Financial Statements. The following table summarizes our proportionate ownership interest in jointly-owned power plants:
As of December 31, 2012 |  | Ownership Interest |  | Property, Plant & Equipment |  | Accumulated Depreciation |  | Construction in Progress
(in millions, except percentages)
Freestone Energy Center |  | 75.0 | % |  | $ | 392 |  |  | $ | (124 | ) |  | $ | 1 |
Hidalgo Energy Center |  | 78.5 | % |  | $ | 252 |  |  | $ | (86 | ) |  | $ | — |
Schedule of Components of Restricted Cash | The table below represents the components of our restricted cash as of December 31, 2012 and 2011 (in millions):
| 2012 |  | 2011
| Current |  | Non-Current |  | Total |  | Current |  | Non-Current |  | Total
Debt service(1) | $ | 11 |  |  | $ | 41 |  |  | $ | 52 |  |  | $ | 11 |  |  | $ | 42 |  |  | $ | 53 |
Construction/major maintenance | 32 |  |  | 14 |  |  | 46 |  |  | 33 |  |  | 10 |  |  | 43 |
Security/project/insurance | 101 |  |  | 3 |  |  | 104 |  |  | 79 |  |  | — |  |  | 79 |
Other | 49 |  |  | 2 |  |  | 51 |  |  | 16 |  |  | 3 |  |  | 19 |
Total | $ | 193 |  |  | $ | 60 |  |  | $ | 253 |  |  | $ | 139 |  |  | $ | 55 |  |  | $ | 194 |
___________
(1) | At both December 31, 2012 and 2011, amounts restricted for debt service included approximately $25 million of repurchase agreements with a financial institution containing maturity dates greater than one year.
Schedule of Total Contractual Future Minimum Lease Receipts | Leases — We have contracts, such as certain tolling agreements, which we account for as operating leases under U.S. GAAP. Generally, we levelize certain components of these contract revenues on a straight-line basis over the term of the contract. The total contractual future minimum lease rentals for our contracts accounted for as operating leases, excluding tolling agreements related to power plants under construction, at December 31, 2012, are as follows (in millions):
2013 | $ | 548 |
2014 | 446 |
2015 | 455 |
2016 | 397 |
2017 | 359 |
Thereafter | 2,078 |
Total | $ | 4,283 |
Future minimum lease payments under these leases are as follows (in millions):
| Initial Year |  | 2013 |  | 2014 |  | 2015 |  | 2016 |  | 2017 |  | Thereafter |  | Total
Land and other operating leases | various |  | $ | 14 |  |  | $ | 14 |  |  | $ | 14 |  |  | $ | 15 |  |  | $ | 15 |  |  | $ | 228 |  |  | $ | 300 |
Power plant operating leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Greenleaf | 1998 |  | $ | 7 |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 10 |
KIAC | 2000 |  | 24 |  |  | 24 |  |  | 23 |  |  | 22 |  |  | 22 |  |  | 52 |  |  | 167 |
Total power plant leases |  |  | $ | 31 |  |  | $ | 27 |  |  | $ | 23 |  |  | $ | 22 |  |  | $ | 22 |  |  | $ | 52 |  |  | $ | 177 |
Total leases |  |  | $ | 45 |  |  | $ | 41 |  |  | $ | 37 |  |  | $ | 37 |  |  | $ | 37 |  |  | $ | 280 |  |  | $ | 477 |

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- Definition Tabular disclosure of future minimum payments required in the aggregate and for each of the five succeeding fiscal years for operating leases having initial or remaining noncancelable lease terms in excess of one year and the total minimum rentals to be received in the future under noncancelable subleases as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Tabular disclosure of proportionate interests in jointly owned utility plants. Includes the amount of plants in service, the accumulated provision for depreciation (if available), the amount of plants under construction, and the proportionate share. The amounts presented may be further subdivided to show amounts applicable to plant subcategories (for example, production, transmission, distribution). Includes statements that the amounts represent the utility's share in each joint plant and that it must provide its own financing. Information concerning two or more generating plants on the same site may be combined. States that the utility's share of direct expenses of the joint plants is included in the corresponding operating expenses on its income statement (for example, fuel, maintenance of plant, other operating expense). If the share of direct expenses is charged to purchased power, then disclose the amount so charged and the proportionate amounts charged to specific operating expenses on the records maintained for the joint plants. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 10.C) -URI http://asc.fasb.org/extlink&oid=6500719&loc=d3e659983-123033 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 10 -Section C + Details
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- Definition Tabular disclosure of the cash and cash items which are restricted as to withdrawal or usage. The provisions of any restrictions are described in a note to the financial statements. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -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 + Details
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