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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - INVESTMENTS IN EQUTIY SECURITIES (Details) shares in Thousands, $ in Thousands |  | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Nov. 26, 2018 | Dec. 31, 2018 USD ($) shares | Dec. 31, 2017 USD ($) | Sep. 30, 2018 USD ($) | Oct. 01, 2018 USD ($)
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Investments in equity securities |  |  |  | $ 32,900 |
Accumulated other comprehensive loss, net of tax |  | $ (15,822) |  | (12,610) |
Equity securities, fv-ni, unrealized gain (loss) |  | 257 |  | 3,400 |
Investments in equity securities |  | 33,174 |  | $ 32,917 |
Debt conversion ratio | 0.2492 |  |  |  |
Proceeds from sale of investments in equity securities, net |  | $ 0 | $ 6,616 |  |
Pre-tax gain on sale of equity securities |  |  | $ 5,300 |  |
Investments in Equity Securities |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Accumulated other comprehensive loss, net of tax |  |  |  |  | $ 4,700
Common Units [Member] |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Other ownership interests, units issued | shares |  | 1,840 |  |  |
Dominion Shares [Member] |  |  |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |  |  |
Other ownership interests, units issued | shares |  | 458 |  |  |

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: 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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669686-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e681-108580 + Details
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- Definition Amount of equity securities categorized neither as held-to-maturity nor as trading. + References No definition available. + Details
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- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. + References No definition available. + Details
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- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 + Details
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- Definition Amount of 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 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740 + Details
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