ACCUMULATED OTHER COMPREHENSIVE LOSS (Changes in Accumulated Other Comprehensive Loss by Component) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Components of Other Accumulated Income, Net of Tax [Roll Forward]
Balance at beginning of period	$ 1,084,241,000
Other comprehensive income before reclassifications	6,057,000
Amounts reclassified out of accumulated other comprehensive loss	146,000	$ 0
Tax effects	(152,000)
Other comprehensive income	6,051,000
Balance at end of period	1,063,630,000
Foreign Currency Translation
Components of Other Accumulated Income, Net of Tax [Roll Forward]
Balance at beginning of period	(212,211,000)
Other comprehensive income before reclassifications	5,823,000
Amounts reclassified out of accumulated other comprehensive loss	0
Tax effects	0
Other comprehensive income	5,823,000
Balance at end of period	(206,388,000)
Unrealized Gains on Available-For-Sale Securities
Components of Other Accumulated Income, Net of Tax [Roll Forward]
Balance at beginning of period	(321,000)
Other comprehensive income before reclassifications	234,000
Amounts reclassified out of accumulated other comprehensive loss	146,000
Tax effects	(152,000)
Other comprehensive income	228,000
Balance at end of period	(93,000)
Unfunded Pension Liability
Components of Other Accumulated Income, Net of Tax [Roll Forward]
Balance at beginning of period	(1,794,000)
Other comprehensive income before reclassifications	0
Amounts reclassified out of accumulated other comprehensive loss	0
Tax effects	0
Other comprehensive income	0
Balance at end of period	(1,794,000)
Total
Components of Other Accumulated Income, Net of Tax [Roll Forward]
Balance at beginning of period	(214,326,000)
Balance at end of period	$ (208,275,000)