Restructuring and Other Charges (Narrative) (Details)	9 Months Ended
Sep. 30, 2018
Lease contract termination and other charges
Restructuring Cost and Reserve [Line Items]
Date amounts attributable to lease contract termination charges will be paid until	Jan. 31, 2022

Date the exit and disposal activities were completed or are expected to be completed, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(a))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration