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Fair Value Measurements (Narratives) (Details) - USD ($) |  | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 01, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Jun. 30, 2018
Assets |  |  |  |  |  |
Change in unrealized gains on available for sale securities |  |  | $ 54,000 |  | $ 237,000 |
ASU 2016-01 |  |  |  |  |  |
Assets |  |  |  |  |  |
Change in unrealized gains on available for sale securities | $ 500,000 |  |  |  |  |
Level 1 Investments |  |  |  |  |  |
Assets |  |  |  |  |  |
Unrealized holding gain on investments |  |  |  |  |  | $ 500,000
Level 2 Assets and Liabilities |  |  |  |  |  |
Assets |  |  |  |  |  |
Transfers of assets between Level 1 and Level 2 |  | $ 0 |  | $ 0 |  | 0
Transfers of liabilities between Level 1 and Level 2 |  | 0 |  | 0 |  | 0
Long-term debt, fair value |  | 185,300,000 |  | 185,300,000 |  | $ 200,000,000
Level 3 Assets and Liabilities |  |  |  |  |  |
Assets |  |  |  |  |  |
Transfers of assets between Level 2 and Level 3 |  | 0 | 0 | 0 | 0 |
Transfers of liabilities between Level 2 and Level 3 |  | 0 | 0 | 0 | 0 |
Intangible asset and goodwill impairment |  | $ 0 | $ 0 | $ 0 | $ 0 |

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- Definition Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714 + Details
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- Definition Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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