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LONG TERM DEBT (Details) - Integrys Holding - Integrys Junior Notes due 2066 - USD ($) $ in Millions | May 14, 2018 | Mar. 31, 2018
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Debt Instrument [Line Items] |  |
Long-term debt, current portion |  | $ 114.9
Subsequent event |  |
Debt Instrument [Line Items] |  |
Extinguishment of debt | $ 114.9 |

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- Definition Gross amount of debt extinguished. + References No definition available. + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + 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 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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