Restructuring (Narrative) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Restructuring and Related Activities [Abstract]
Non-cash restructuring charges relating to impairment of long-lived assets	$ 4,500
Accrued restructuring costs expected to be paid within one year	4,000
Accrued restructuring costs expected to be paid in year two	$ 400

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Name:	us-gaap_RestructuringCostsAndAssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration