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NON-U.S. EMPLOYEE DEFINED BENEFIT PLANS - Narrative (Details) - USD ($) | 2 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018
Retirement Benefits [Abstract] |  |  |
Curtailment gain |  |  | $ 500,000
Benefits paid | $ 3,000 | $ 683,000 | 273,000
One-time lump sum payments to participants |  | $ 660,000 | 250,000
Net gains and losses amortization threshold |  | 10.00% |
Expected amortization of gain (loss) in the next fiscal year |  | $ 176,000 |
Fair value of combined plan assets | 3,893,000 | 1,830,000 | 3,842,000
Participant contributions | $ 5,000 | 24,000 | 5,000
Fixed contributions per employee, percent | 5.00% |  |
Employer pension plan contributions | $ 22,000 | 139,000 | $ 292,000
Expected future employer contributions to pension plans in 2020 |  | $ 200,000 |

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- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/exampleRef -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 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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