Employee Benefits (Narrative) (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)
Pension Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions by Employer		$ 5.0
SERP [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions by Employer		0.2
Estimated Future Employer Contributions in Current Fiscal Year	$ 0.3	0.3
Medical Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions by Employer		0.1
Estimated Future Employer Contributions in Current Fiscal Year	0.2	0.2
401(k) Plan [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions by Employer		2.6
Estimated Future Employer Contributions in Current Fiscal Year	1.8	1.8
Pension Plan Discretionary Contribution [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated Future Employer Contributions in Current Fiscal Year	0.1	0.1
Total [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and Medical Plan curtailment	0.1	(0.4)
Interest and other income (expense) [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and Medical Plan curtailment	0.1	(0.2)
Net gain (loss) from asset sales [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and Medical Plan curtailment	$ 0.0	(0.2)
Restructuring Charges [Member] | Total [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and Medical Plan curtailment		0.1
Net gain (loss) from asset sales [Member] | Total [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension and Medical Plan curtailment		$ (0.5)