EMPLOYEE BENEFIT PLANS - Retirement Income Plan (Details) - USD ($) |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Period based on which benefits are based on the highest average compensation during last ten years | 5 years | ||
| Company contributions to defined contribution plan | $ 12,100,000 | $ 11,000,000 | $ 10,200,000 |
| Benefits paid | 10,225,000 | 18,634,000 | |
| Retirement Income Plan | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Company contributions to defined contribution plan | 0 | 3,300,000 | $ 5,000,000 |
| Single-sum payment for the ability to elect for a limited time the commencement of benefit | $ 0 | ||
| Benefits paid | $ 8,800,000 | ||
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- Definition Defined Benefit Plan, Benefits Based on Specified Period of Highest Average Compensation During Last Ten Years No definition available.
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- Definition Defined Benefit Plan Single Sum to be Paid by Vested Terminated Participants for Electing Limited Time for Commencement of Benefits No definition available.
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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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