v2.4.0.8

Commitments and Contingencies (Schedules of Future Minimum Rental Payments) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Land and Other Operating Leases [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | $ 290 |  |  |
Operating Leases, Future Minimum Payments Due, Current | 15 |  |  |
Operating Leases, Future Minimum Payments, Due in Two Years | 15 |  |  |
Operating Leases, Future Minimum Payments, Due in Three Years | 15 |  |  |
Operating Leases, Future Minimum Payments, Due in Four Years | 15 |  |  |
Operating Leases, Future Minimum Payments, Due in Five Years | 15 |  |  |
Operating Leases, Future Minimum Payments, Due Thereafter | 215 |  |  |
Greenleaf [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | 11 |  |  |
KIAC [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | 143 |  |  |
Operating Leases, Future Minimum Payments Due, Current | 24 |  |  |
Operating Leases, Future Minimum Payments, Due in Two Years | 23 |  |  |
Operating Leases, Future Minimum Payments, Due in Three Years | 22 |  |  |
Operating Leases, Future Minimum Payments, Due in Four Years | 22 |  |  |
Operating Leases, Future Minimum Payments, Due in Five Years | 22 |  |  |
Operating Leases, Future Minimum Payments, Due Thereafter | 30 |  |  |
Total Power Plant Leases [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | 154 |  |  |
Operating Leases, Future Minimum Payments Due, Current | 31 |  |  |
Operating Leases, Future Minimum Payments, Due in Two Years | 27 |  |  |
Operating Leases, Future Minimum Payments, Due in Three Years | 22 |  |  |
Operating Leases, Future Minimum Payments, Due in Four Years | 22 |  |  |
Operating Leases, Future Minimum Payments, Due in Five Years | 22 |  |  |
Operating Leases, Future Minimum Payments, Due Thereafter | 30 |  |  |
Operating Leases, Rent Expense, Net | 47 |  | 51 | 53
Operting Lease Assets Total [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | 444 |  |  |
Operating Leases, Future Minimum Payments Due, Current | 46 |  |  |
Operating Leases, Future Minimum Payments, Due in Two Years | 42 |  |  |
Operating Leases, Future Minimum Payments, Due in Three Years | 37 |  |  |
Operating Leases, Future Minimum Payments, Due in Four Years | 37 |  |  |
Operating Leases, Future Minimum Payments, Due in Five Years | 37 |  |  |
Operating Leases, Future Minimum Payments, Due Thereafter | 245 |  |  |
Office Equipment [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | 80 |  |  |
Operating Leases, Future Minimum Payments Due, Current | 11 |  |  |
Operating Leases, Future Minimum Payments, Due in Two Years | 10 |  |  |
Operating Leases, Future Minimum Payments, Due in Three Years | 10 |  |  |
Operating Leases, Future Minimum Payments, Due in Four Years | 11 |  |  |
Operating Leases, Future Minimum Payments, Due in Five Years | 10 |  |  |
Operating Leases, Future Minimum Payments, Due Thereafter | 28 |  |  |
Operating Leases, Rent Expense, Net | 12 |  | 12 | 13
Greenleaf [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Guarantee Obligations Balance On First Anniversary | 7 | [1] |  |
Guarantee Obligations Balance On Second Anniversary | 4 | [1] |  |
Guarantee Obligations Balance On Third Anniversary | 0 | [1] |  |
Guarantee Obligations Balance On Fourth Anniversary | 0 | [1] |  |
Guarantee Obligations Balance On Fifth Anniversary | 0 | [1] |  |
Guarantee Obligations Due After Five Years | 0 | [1] |  |
Natural Gas [Member] |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |
Operating Leases, Future Minimum Payments Due | 2,187 |  |  |
Operating Leases, Future Minimum Payments Due, Current | 385 |  |  |
Operating Leases, Future Minimum Payments, Due in Two Years | 290 |  |  |
Operating Leases, Future Minimum Payments, Due in Three Years | 238 |  |  |
Operating Leases, Future Minimum Payments, Due in Four Years | 235 |  |  |
Operating Leases, Future Minimum Payments, Due in Five Years | 224 |  |  |
Operating Leases, Future Minimum Payments, Due Thereafter | $ 815 |  |  |
[1] | These are contingent off balance sheet obligations.

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- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 10 -Section 55 -Paragraph 40 -Subparagraph (Note 3) -URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717 + Details
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- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41499-112717 + Details
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