PENSION AND POST RETIREMENT BENEFIT PLANS - Net Periodic Benefit (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
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| Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] | ||||
| Interest and service cost | $ 1,995 | $ 2,138 | $ 3,990 | $ 4,276 |
| Expected return on plan assets | (3,443) | (3,342) | (6,886) | (6,684) |
| Amortization of net loss | 826 | 830 | 1,652 | 1,660 |
| Net periodic benefit | $ (622) | $ (374) | $ (1,244) | $ (748) |
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- Definition Defined Benefit Plan Interest and Service Cost No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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