Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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SHORT-TERM DEBT AND LINES OF CREDIT - REVOLVING CREDIT FACILITIES (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Revolving credit facilities
Short-term credit capacity	$ 3,100.0
Available capacity under existing credit facility	1,649.4
Letter of credit
Revolving credit facilities
Letters of credit issued inside credit facilities	2.3
Commercial paper
Revolving credit facilities
Commercial paper outstanding	1,448.3	$ 1,896.1
WE \| Credit facility maturing in September 2026
Revolving credit facilities
Short-term credit capacity	500.0
WPS \| Credit facility maturing in September 2026
Revolving credit facilities
Short-term credit capacity	400.0
WG \| Credit facility maturing in September 2026
Revolving credit facilities
Short-term credit capacity	350.0
PGL \| Credit facility maturing in September 2026
Revolving credit facilities
Short-term credit capacity	350.0
WEC Energy Group \| Credit facility maturing in September 2026
Revolving credit facilities
Short-term credit capacity	$ 1,500.0