Pension Plans and Other Postretirement Benefits Pension and Postretirement Plan Contributions (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Compensation and Retirement Disclosure [Abstract]
Pension contributions	$ 4.5	$ 4.5	$ 7.9	$ 9.1
Other postretirement benefits payments	$ 0.8	$ 0.5	$ 1.6	$ 1.9

The amount of cash or cash equivalents contributed during the reporting period by the entity to fund non-pension postretirement benefits.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

Name:	us-gaap_OtherPostretirementBenefitsPayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration