Schedule I - Short-Term Notes Payable to Related Parties (Details) - WEC Energy Group - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Notes to parent company financial statements
Short-term notes payable to related parties	$ 220.4	$ 303.0
WBS
Notes to parent company financial statements
Short-term notes payable to related parties	107.7	149.0
WECC
Notes to parent company financial statements
Short-term notes payable to related parties	107.4	110.0
Integrys
Notes to parent company financial statements
Short-term notes payable to related parties	5.3	0.0
Bluewater
Notes to parent company financial statements
Short-term notes payable to related parties	$ 0.0	$ 44.0

The amount for notes payable (written promise to pay), due to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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Balance Type:	credit
Period Type:	instant