EMPLOYEE BENEFITS (Change in Fair Value of Pension Plan Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Pension Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	$ 157,644	$ 128,430
Fair value of plan assets at end of year	164,819	157,644
U.S. property separate account fund \| Pension Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	15,502
Fair value of plan assets at end of year	20,841	15,502
U.S. property separate account fund \| Level 3
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Company contribution	4,000
U.S. property separate account fund \| Level 3 \| Pension Benefits
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of year	15,502	14,330
Unrealized gains	1,339	1,172
Fair value of plan assets at end of year	$ 20,841	$ 15,502

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount, measured using unobservable input, of increase in plan asset of defined benefit plan from purchase.

+ References

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