Long-Term Debt - Debt Maturing Within One Year (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Long-term debt maturing within one year
2022	$ 91.0
2023	793.8
2024	1,222.7
2025	865.9
2026	104.2
Thereafter	10,575.0
Long-term Debt, Gross	$ 13,652.6	$ 12,529.2
2.95% WE debentures \| WE
Long-term debt maturing within one year
Interest rate	1.58%
Principal amount of unsecured debt	$ 8.8
3.76% Bluewater Gas Storage senior notes \| Bluewater Gas Storage
Long-term debt maturing within one year
Interest rate	3.76%
Principal amount of senior notes	$ 2.7
4.91% We Power subsidiaries notes - PWGS \| We Power
Long-term debt maturing within one year
Interest rate	4.91%
Principal amount of secured debt	$ 7.2
5.209% We Power subsidiaries notes - ERGS \| We Power
Long-term debt maturing within one year
Interest rate	5.209%
Principal amount of secured debt	$ 13.9
4.673% We Power subsidiaries notes - ERGS \| We Power
Long-term debt maturing within one year
Interest rate	4.673%
Principal amount of secured debt	$ 10.7
6.00% We Power subsidiaries notes - PWGS \| We Power
Long-term debt maturing within one year
Interest rate	6.00%
Principal amount of secured debt	$ 6.2
2.75% WECI Wind Holding I senior notes \| WECI Wind Holding I
Long-term debt maturing within one year
Interest rate	2.75%
Principal amount of senior notes	$ 41.5

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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