Pension and Other Postretirement Benefit Plans (Tables)

3 Months Ended

Mar. 31, 2016

Compensation and Retirement Disclosure [Abstract]

Components of Net Periodic Benefit Expense (Income) [Table Text Block]

	Pension						Other Postretirement
Components of Net Periodic Benefit Expense (Income)	2016			2015			2016			2015
Millions
Three Months Ended March 31,
Service Cost		$2.0			$2.5			$1.0			$1.1
Interest Cost	8.1			7.5			1.9			1.8
Expected Return on Plan Assets	(10.6		)	(10.2		)	(2.8		)	(2.7		)
Amortization of Prior Service Credits	—			—			(0.7		)	(0.8		)
Amortization of Net Loss	2.4			4.5			—			0.1
Net Periodic Benefit Expense (Income)		$1.9			$4.3		$(0.6)			$(0.5)