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Schedule I - Short-Term Notes Receivable from Related Parties (Details) - WEC Energy Group - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Notes to parent company financial statements |  |
Short-term notes receivable from related parties | $ 64.1 | $ 76.4
UMERC |  |
Notes to parent company financial statements |  |
Short-term notes receivable from related parties | 38.1 | 0.0
Wispark |  |
Notes to parent company financial statements |  |
Short-term notes receivable from related parties | 26.0 | 15.9
Integrys |  |
Notes to parent company financial statements |  |
Short-term notes receivable from related parties | 0.0 | 42.0
Bostco |  |
Notes to parent company financial statements |  |
Short-term notes receivable from related parties | $ 0.0 | $ 18.5

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