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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Recent Accounting Pronouncements (Details) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 USD ($) | Dec. 31, 2018 USD ($) lease | Dec. 31, 2016 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Equity investment portfolio balance | $ 3,000 |  |
Right of use leased asset | 5,572 |  | $ 5,572
Reclassification of stranded tax effects in AOCI | 0 |  |
Adjustments for New Accounting Principle, Early Adoption |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Reclassification of stranded tax effects in AOCI | $ 1,800 |  |
Scenario, Forecast | Accounting Standards Update 2016-02 |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Right of use leased asset |  | $ 10,000 |
Number of leased facilities | lease |  | 15 |

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- Definition Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect + References No definition available. + Details
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- Definition Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84164758&loc=d3e45014-112735 + Details
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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