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EMPLOYEE BENEFIT PLANS - Plan assets using fair value hierarchy (Details) - Retirement Income Plan - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
EMPLOYEE BENEFIT PLANS |  |
Investments Measured at Net Asset Value | $ 514 | $ 638
Investments at Fair Value | 7,314 | 6,802
Cash and Cash Equivalents |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 92 | 202
Cash and Cash Equivalents | Quoted prices in active markets for identical assets (Level 1) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 92 | 202
Fixed Income Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 6,708 | 1,979
Fixed Income Securities | Significant other observable inputs (Level 2) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 6,708 | 1,979
Domestic Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy |  | 2,693
Domestic Equity Securities | Quoted prices in active markets for identical assets (Level 1) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy |  | 993
Domestic Equity Securities | Significant other observable inputs (Level 2) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy |  | 1,700
International Equity Securities |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy |  | 1,290
International Equity Securities | Significant other observable inputs (Level 2) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy |  | 1,290
Investment |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 6,800 | 6,164
Investment | Quoted prices in active markets for identical assets (Level 1) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | 92 | 1,195
Investment | Significant other observable inputs (Level 2) |  |
EMPLOYEE BENEFIT PLANS |  |
Total Assets in the Fair Value Hierarchy | $ 6,708 | $ 4,969

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- Definition Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=SL6742756-110258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 35 -Paragraph 54B -URI http://asc.fasb.org/extlink&oid=117332851&loc=SL7495116-110257 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of investment within defined benefit plan asset category. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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