Dispositions (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Wisconsin | WE
Dispositions
After-tax gain (loss) on sale	$ 6.5
Wisconsin | WE | Other operation and maintenance
Dispositions
Pre-tax gain (loss) on sale	10.9
Corporate and Other | Wisvest
Dispositions
After-tax gain (loss) on sale	11.8
Corporate and Other | Wisvest | Other income, net
Dispositions
Pre-tax gain (loss) on sale	$ 19.6
Corporate and Other | ITF
Dispositions
Pre-tax gain (loss) on sale		$ 0.0
Assets and liabilities included in held for sale
Property, plant, and equipment			$ 37.2
Accounts receivable and unbilled revenues			34.9
Materials, supplies, and inventories			18.4
Other current assets			2.6
Other long-term assets			3.7
Total assets			96.8
Accounts payable			12.9
Accrued payroll and benefits			2.4
Other current liabilities			4.5
Pension and OPEB obligations			1.2
Other long-term liabilities			0.6
Total liabilities			$ 21.6