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Natural gas costs recoverable or refundable through rate adjustments (Details 10) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Dec. 31, 2012 | Dec. 31, 2011
Minimum period over which natural gas costs greater or less than amounts being recovered become recoverable or refundable through rate adjustments | 12 months |
Maximum period over which natural gas costs greater or less than amounts being recovered become recoverable or refundable through rate adjustments | 28 months |
Natural gas costs refundable | $ 35.3 | $ 45.1
Natural gas costs recoverable | $ 3.0 | $ 2.6

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- Definition Maximum period over which natural gas costs greater or less than amounts being recovered through existing rate schedules become recoverable or refundable through rate adjustments. + References No definition available. + Details
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- Definition Minimum period over which natural gas costs greater or less than amounts being recovered through existing rate schedules become recoverable or refundable through rate adjustments. + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of capitalized gas costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 9 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499739&loc=d3e43603-110378 + Details
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- Definition Gas costs of a regulated entity that are refundable through future rate adjustments. Such costs are a form of a regulatory liabilities and are expected to be refunded in less than one year through rate adjustments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 11 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 405 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394 + Details
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