Basis of Presentation (Basis of Presentation) (Details)	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017
Basis of Presentation [Line Items]
Operating Cycle		52
Scenario, Forecast [Member]
Basis of Presentation [Line Items]
Operating Cycle	52

Entity's operating cycle if it is other than 12 months.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473108&loc=d3e54406-107959

Name:	us-gaap_OperatingCycle
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration