v3.4.0.3

Commitments and Contingencies - Environmental Matters (Details) T in Millions, $ in Millions	1 Months Ended					3 Months Ended	12 Months Ended
	Jan. 31, 2016	Dec. 31, 2015 USD ($)	Aug. 31, 2014	Apr. 30, 2013	Mar. 31, 2013 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) T	Jun. 01, 2015 USD ($)
Mercury and Other Hazardous Air Pollutants | Electric
Air quality
Percentage of mercury emissions reduction required by Wisconsin and Michigan						90.00%
Mercury and Other Hazardous Air Pollutants | Electric | WE
Air quality
Term of Mercury and Air Toxics Standards (MATS) compliance extension				1 year
Mercury and Other Hazardous Air Pollutants | Electric | WPS
Air quality
Term of Mercury and Air Toxics Standards (MATS) compliance extension						1 year
Climate Change | Electric
Air quality
Percentage of greenhouse gas emissions reduction nationwide							32.00%
Percentage of greenhouse gas emissions reduction for retirement of a nuclear plant		10.00%
Carbon dioxide emissions | T							31.0
Climate Change | Electric | Wisconsin
Air quality
Percentage of greenhouse gas emissions reduction by state							41.00%
Climate Change | Electric | Michigan
Air quality
Percentage of greenhouse gas emissions reduction by state							39.00%
Climate Change | Natural gas
Air quality
Carbon dioxide emissions | T							27.2
Clean Water Act Cooling Water Intake Structure Rule | Electric
Water quality
Number of compliance options available to meet standard			7
Steam Electric Effluent Guidelines | Electric
Water quality
Renewal period for facility permits	5 years
Steam Electric Effluent Guidelines | Minimum | Electric
Water quality
Expected environmental costs to achieve required emission reductions						$ 95.0
Steam Electric Effluent Guidelines | Maximum | Electric
Water quality
Expected environmental costs to achieve required emission reductions						130.0
Manufactured Gas Plant Remediation | Natural gas
Manufactured gas plant remediation
Regulatory assets recorded for cash and estimated future remediation expenditures		$ 697.0				683.7	$ 697.0
Liabilities estimated and accrued for future undiscounted investigation and cleanup costs for all sites		$ 628.0				$ 617.5	$ 628.0
Weston and Pulliam Consent Decree | Electric | WPS
Consent decrees
Regulatory asset for undepreciated book value of retired plants								$ 11.5
Civil penalty					$ 1.2

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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