Commitments and Contingencies Commitments and Contingencies (Voluntary Recall) (Details) $ in Millions	Dec. 31, 2017 USD ($)
Accrued Liabilities \| Voluntary Recall [Member]
Product Liability Contingency [Line Items]
Accrual for voluntary recall	$ 29.4

Recorded amount of the accrual for a material component of a product liability contingency.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

Name:	us-gaap_ProductLiabilityAccrualComponentAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant