Revenue earned during the period from non-repayable sum of money awarded to an entity to carry out a specific purpose as provided in grant agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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

Business Realignment and Corporate Headquarter Relocation (Narrative) (Details) - Corporate Headquarter Relocation [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Apr. 25, 2016
Selling, General and Administrative Expenses [Member]
Restructuring Cost and Reserve [Line Items]
Headquarter relocation costs	$ 726		$ 998
Grant income		$ 338
Maximum [Member]
Restructuring Cost and Reserve [Line Items]
Grant awarded				$ 1,400