EMPLOYEE BENEFITS (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance at end of year	$ 185,981	$ 193,429
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Pension and postretirement liabilities	(53,119)	(28,188)
Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	216,306	223,780
Service cost	1,421	1,401	1,246
Interest cost	8,426	7,380	8,159
Plan participants' contributions	1,501	1,567
Actuarial loss (gain)	34,840	(12,208)
Foreign currency impact	(11,792)	2,463
Benefits and administrative expenses paid	(11,985)	(7,760)
Settlements	(3,284)	(628)
Acquisitions	0	311
Benefit obligation at end of year	235,433	216,306	223,780
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance at beginning of year	193,429	176,693
Actual return on plan assets	14,688	18,233
Employer contributions	2,644	2,732
Foreign currency impact	(11,012)	2,592
Balance at end of year	185,981	193,429	176,693
Funded status of plans	(49,452)	(22,877)
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Non-current assets	2,318	4,023
Current liabilities	(253)	(232)
Pension and postretirement liabilities	(51,517)	(26,668)
Net amount recognized	(49,452)	(22,877)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax [Abstract]
Net actuarial (loss) gain	(75,220)	(50,580)
Transition asset	500	850
Prior service credit	2,126	3,232
Accumulated other comprehensive (loss) income	(72,594)	(46,498)
Accumulated contributions in excess of net periodic benefit cost	23,142	23,621
Net amount recognized	(49,452)	(22,877)
Defined Benefit Plan, Settlements, Plan Assets	3,284	628
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of year	1,769	2,312
Service cost	11	18	18
Interest cost	87	92	111
Plan participants' contributions	326	375
Actuarial loss (gain)	10	(452)
Foreign currency impact	0	0
Benefits and administrative expenses paid	(397)	(604)
Settlements	0	0
Acquisitions	0	28
Benefit obligation at end of year	1,806	1,769	2,312
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Balance at beginning of year	0	0
Actual return on plan assets	0	0
Employer contributions	71	229
Foreign currency impact	0	0
Balance at end of year	0	0	0
Funded status of plans	(1,806)	(1,769)
Defined Benefit Plan, Amounts Recognized in Balance Sheet [Abstract]
Non-current assets	0	0
Current liabilities	(112)	(131)
Pension and postretirement liabilities	(1,694)	(1,638)
Net amount recognized	(1,806)	(1,769)
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net of Tax [Abstract]
Net actuarial (loss) gain	657	724
Transition asset	0	0
Prior service credit	0	0
Accumulated other comprehensive (loss) income	657	724
Accumulated contributions in excess of net periodic benefit cost	(2,463)	(2,493)
Net amount recognized	(1,806)	(1,769)
Defined Benefit Plan, Settlements, Plan Assets	$ 0	$ 0