Consolidated Statements of Capitalization - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Common shareholder's equity	$ 9,491.8	$ 8,960.2
Preferred stock of subsidiary	30.4	30.4
Obligations under capital leases	27.0	29.6
Total	9,627.9	9,352.0
Integrys acquisition fair value adjustment	26.9	33.3
Unamortized debt issuance costs	(38.0)	(38.1)
Unamortized discount, net and other	(28.1)	(31.8)
Total long-term debt, including current portion	9,588.7	9,315.4
Current portion of long-term debt and capital lease obligations	(842.1)	(157.2)
Total long-term debt	8,746.6	9,158.2
Total long-term capitalization	$ 18,238.4	$ 18,118.4
WEC Energy Group Junior Notes (unsecured), 3.53% due 2067
Interest rate, (as a percent)	3.53%
Integrys Junior Notes (unsecured), 3.60% due 2066
Interest rate, (as a percent)	3.60%	3.05%
WE \| WE Debentures (unsecured), 1.70% due 2018
Interest rate, (as a percent)	1.70%
Long-Term debt, Unsecured	$ 250.0	$ 250.0
WE \| WE Debentures (unsecured), 4.25% due 2019
Interest rate, (as a percent)	4.25%
Long-Term debt, Unsecured	$ 250.0	250.0
WE \| WE Debentures (unsecured), 2.95% due 2021
Interest rate, (as a percent)	2.95%
Long-Term debt, Unsecured	$ 300.0	300.0
WE \| WE Debentures (unsecured), 3.10% due 2025
Interest rate, (as a percent)	3.10%
Long-Term debt, Unsecured	$ 250.0	250.0
WE \| WE Debentures (unsecured), 6.50% due 2028
Interest rate, (as a percent)	6.50%
Long-Term debt, Unsecured	$ 150.0	150.0
WE \| WE Debentures (unsecured), 5.625% due 2033
Interest rate, (as a percent)	5.625%
Long-Term debt, Unsecured	$ 335.0	335.0
WE \| WE Debentures (unsecured), 5.70% due 2036
Interest rate, (as a percent)	5.70%
Long-Term debt, Unsecured	$ 300.0	300.0
WE \| WE Debentures (unsecured), 3.65% due 2042
Interest rate, (as a percent)	3.65%
Long-Term debt, Unsecured	$ 250.0	250.0
WE \| WE Debentures (unsecured), 4.25% due 2044
Interest rate, (as a percent)	4.25%
Long-Term debt, Unsecured	$ 250.0	250.0
WE \| WE Debentures (unsecured), 4.30% due 2045
Interest rate, (as a percent)	4.30%
Long-Term debt, Unsecured	$ 250.0	250.0
WE \| WE Debentures (unsecured), 6.875% due 2095
Interest rate, (as a percent)	6.875%
Long-Term debt, Unsecured	$ 100.0	100.0
WPS \| WPS Senior Notes (unsecured), 5.65% due 2017
Interest rate, (as a percent)	5.65%
Long-Term debt, Unsecured	$ 0.0	125.0
WPS \| WPS Senior Notes (unsecured), 1.65% due 2018
Interest rate, (as a percent)	1.65%
Long-Term debt, Unsecured	$ 250.0	250.0
WPS \| WPS Senior Notes (unsecured), 6.08% due 2028
Interest rate, (as a percent)	6.08%
Long-Term debt, Unsecured	$ 50.0	50.0
WPS \| WPS Senior Notes (unsecured), 5.55% due 2036
Interest rate, (as a percent)	5.55%
Long-Term debt, Unsecured	$ 125.0	125.0
WPS \| WPS Senior Notes (unsecured), 3.671% due 2042
Interest rate, (as a percent)	3.671%
Long-Term debt, Unsecured	$ 300.0	300.0
WPS \| WPS Senior Notes (unsecured), 4.752% due 2044
Interest rate, (as a percent)	4.752%
Long-Term debt, Unsecured	$ 450.0	450.0
WG \| WG Debentures (unsecured), 3.53% due 2025
Interest rate, (as a percent)	3.53%
Long-Term debt, Unsecured	$ 200.0	200.0
WG \| WG Debentures (unsecured), 5.90% due 2035
Interest rate, (as a percent)	5.90%
Long-Term debt, Unsecured	$ 90.0	90.0
WG \| WG Debentures (unsecured), 3.71% due 2046
Interest rate, (as a percent)	3.71%
Long-Term debt, Unsecured	$ 200.0	200.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 8.00% due 2018
Interest rate, (as a percent)	8.00%
Long-Term debt, Secured	$ 5.0	5.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 4.63% due 2019
Interest rate, (as a percent)	4.63%
Long-Term debt, Secured	$ 75.0	75.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 3.90% due 2030
Interest rate, (as a percent)	3.90%
Long-Term debt, Secured	$ 50.0	50.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 1.875% due 2033
Interest rate, (as a percent)	1.875%
Long-Term debt, Secured	$ 50.0	50.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 4.0% due 2033
Interest rate, (as a percent)	4.00%
Long-Term debt, Secured	$ 50.0	50.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 3.98% due 2042
Interest rate, (as a percent)	3.98%
Long-Term debt, Secured	$ 100.0	100.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 3.96% due 2043
Interest rate, (as a percent)	3.96%
Long-Term debt, Secured	$ 220.0	220.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 4.21% due 2044
Interest rate, (as a percent)	4.21%
Long-Term debt, Secured	$ 200.0	200.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 3.65% due 2046
Interest rate, (as a percent)	3.65%
Long-Term debt, Secured	$ 50.0	50.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 3.65% due 2046
Interest rate, (as a percent)	3.65%
Long-Term debt, Secured	$ 150.0	150.0
PGL \| PGL First and Refunding Mortgage Bonds (secured), 3.77% due 2047
Interest rate, (as a percent)	3.77%
Long-Term debt, Secured	$ 100.0	0.0
NSG \| NSG First Mortgage Bonds (secured), 3.43% due 2027
Interest rate, (as a percent)	3.43%
Long-Term debt, Secured	$ 28.0	28.0
NSG \| NSG First Mortgage Bonds (secured), 3.96% due 2043
Interest rate, (as a percent)	3.96%
Long-Term debt, Secured	$ 54.0	54.0
MGU \| MGU Senior Notes (unsecured), 3.11% due 2027
Interest rate, (as a percent)	3.11%
Long-Term debt, Unsecured	$ 30.0	0.0
MGU \| MGU Senior Notes (unsecured), 3.41% due 2032
Interest rate, (as a percent)	3.41%
Long-Term debt, Unsecured	$ 30.0	0.0
MGU \| MGU Senior Notes (unsecured), 4.01% due 2047
Interest rate, (as a percent)	4.01%
Long-Term debt, Unsecured	$ 30.0	0.0
MERC \| MERC Senior Notes (unsecured), 3.11% due 2027
Interest rate, (as a percent)	3.11%
Long-Term debt, Unsecured	$ 40.0	0.0
MERC \| MERC Senior Notes (unsecured), 3.41% due 2032
Interest rate, (as a percent)	3.41%
Long-Term debt, Unsecured	$ 40.0	0.0
MERC \| MERC Senior Notes (unsecured), 4.01% due 2047
Interest rate, (as a percent)	4.01%
Long-Term debt, Unsecured	$ 40.0	0.0
Bluewater Gas Storage, LLC \| Bluewater Gas Storage Senior Notes (unsecured), 3.76% due 2047
Interest rate, (as a percent)	3.76%
Long-Term debt, Unsecured	$ 125.0	0.0
We Power \| We Power Subsidiaries Notes (secured, nonrecourse), 4.91% due 2018-2030
Interest rate, (as a percent)	4.91%
Long-Term debt, Secured	$ 101.0	106.7
We Power \| We Power Subsidiaries Notes (secured, nonrecourse), 5.209% due 2018-2030
Interest rate, (as a percent)	5.209%
Long-Term debt, Secured	$ 194.1	204.8
We Power \| We Power Subsidiaries Notes (secured, nonrecourse), 4.673% due 2018-2031
Interest rate, (as a percent)	4.673%
Long-Term debt, Secured	$ 162.4	170.9
We Power \| We Power Subsidiaries Notes (secured, nonrecourse), 6.00% due 2018-2033
Interest rate, (as a percent)	6.00%
Long-Term debt, Secured	$ 121.5	126.1
We Power \| We Power Subsidiaries Notes (secured, nonrecourse), 6.09% due 2030-2040
Interest rate, (as a percent)	6.09%
Long-Term debt, Secured	$ 275.0	275.0
We Power \| We Power Subsidiaries Notes (secured, nonrecourse), 5.848% due 2031-2041
Interest rate, (as a percent)	5.848%
Long-Term debt, Secured	$ 215.0	215.0
WECC \| WECC Notes (unsecured), 6.94% due 2028
Interest rate, (as a percent)	6.94%
Long-Term debt, Unsecured	$ 50.0	50.0
Integrys Holding Inc \| Integrys Senior Notes (unsecured), 4.17% due 2020
Interest rate, (as a percent)	4.17%
Long-Term debt, Unsecured	$ 250.0	250.0
Integrys Holding Inc \| Integrys Junior Notes (unsecured), 3.60% due 2066
Interest rate, (as a percent)	3.60%
Long-Term debt, Unsecured	$ 114.9	114.9
Integrys Holding Inc \| Integrys Junior Notes (unsecured), 6.00% due 2073
Interest rate, (as a percent)	6.00%
Long-Term debt, Unsecured	$ 400.0	400.0
Bostco \| Other Notes (secured, nonrecourse), 4.81% due 2030
Interest rate, (as a percent)	4.81%
Long-Term debt, Secured	$ 0.0	2.0
WEC Energy Group
Common shareholder's equity	$ 9,461.4	8,929.8
WEC Energy Group \| WEC Energy Group Senior Notes (unsecured), 1.65%, due 2018
Interest rate, (as a percent)	1.65%
Long-Term debt, Unsecured	$ 300.0	300.0
WEC Energy Group \| WEC Energy Group Senior Notes (unsecured), 2.45% due 2020
Interest rate, (as a percent)	2.45%
Long-Term debt, Unsecured	$ 400.0	400.0
WEC Energy Group \| WEC Energy Group Senior Notes (unsecured), 3.55% due 2025
Interest rate, (as a percent)	3.55%
Long-Term debt, Unsecured	$ 500.0	500.0
WEC Energy Group \| WEC Energy Group Senior Notes (unsecured), 6.20% due 2033
Interest rate, (as a percent)	6.20%
Long-Term debt, Unsecured	$ 200.0	200.0
WEC Energy Group \| WEC Energy Group Junior Notes (unsecured), 3.53% due 2067
Interest rate, (as a percent)	3.53%
Long-Term debt, Unsecured	$ 500.0	500.0
Common shareholder's equity
Common shareholder's equity	$ 9,461.4	$ 8,929.8

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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