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LONG-TERM DEBT (Details) - USD ($) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2019 | Jul. 24, 2019
WEC Energy Group | WEC Senior Notes due 2022 |  |
Debt Instrument [Line Items] |  |
Proceeds from Issuance of Debt | $ 350.0 |
Debt instrument stated interest rate percentage | 3.10% |
Subsequent event | ATC Holding LLC | ATC Holding Senior Notes due September 2029 |  |
Debt Instrument [Line Items] |  |
Debt instrument stated interest rate percentage |  | 3.75%
Secured commitment |  | $ 235.0

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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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