Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580

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

Summary of Significant Accounting Policies (Narratives) (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Jul. 01, 2018	Dec. 31, 2017	Dec. 31, 2017
Significant Accounting Policies [Line Items]
Change in unrealized gains on available for sale securities		$ 54	$ 237
ASU 2016-01
Significant Accounting Policies [Line Items]
Change in unrealized gains on available for sale securities	$ 500