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Commitments and Contingencies, Nuclear Insurance (Details) - NSP-Minnesota - Nuclear Insurance $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($) Plant Reactor
Nuclear Insurance [Abstract] |
Nuclear insurance coverage secured for the Company's public liability exposure | $ 450
Nuclear insurance coverage exposure funded by the Secondary Financial Protection Program | 13,600
Maximum assessments per reactor per accident | $ 138
Number of owned and licensed reactors | Reactor | 3
Maximum funding requirement per reactor for any one year | $ 21
Insurance coverage limits for NSP-Minnesota's nuclear plant sites | $ 2,300
Number of nuclear plant sites operated by NSP-Minnesota | Plant | 2
Maximum assessments for business interruption insurance each calendar year | $ 18
Maximum assessment for property damage insurance NSP-Minnesota is subject to each calendar year | 39
Maximum |
Nuclear Insurance [Abstract] |
Loss Contingency, Estimate of Possible Loss | $ 14,100

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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12021-110248 + Details
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- Definition The maximum assessments for business interruption insurance per calendar year if losses exceed accumulated reserve funds. + References No definition available. + Details
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- Definition The maximum assessment for property damage insurance per calendar year if losses exceed accumulated reserve funds. + References No definition available. + Details
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- Definition The maximum assessment the company is subject to for each reactor per accident incurred at any licensed nuclear facility within the United States, collected in annual installments. + References No definition available. + Details
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- Definition The annual maximum installment payment the company is subject to until either the maximum assessment has been reached or the claim has been met. + References No definition available. + Details
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- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
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- Definition The amount of coverage secured for the public liability exposure thru the Secondary Financial Protection Program, available from assessments by the federal government in case of a nuclear accident. + References No definition available. + Details
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- Definition The amount of coverage secured for the public liability exposure thru a pool of insurance companies. + References No definition available. + Details
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- Definition The number of nuclear plant sites operated by the entity. + References No definition available. + Details
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- Definition The number of owned and licensed reactors. + References No definition available. + Details
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- Details
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