OTHER - Components of Accumulated Other Comprehensive Loss, Net (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	$ 263,104,000	$ 265,839,000	$ 279,493,000	$ 210,279,000
Balance at end of year	247,925,000	272,010,000	247,925,000	272,010,000
Accumulated translation adjustment:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	(35,374,000)	(29,930,000)	(33,727,000)	(27,821,000)
Translation (loss) gain during period	(2,385,000)	124,000	(4,032,000)	(1,985,000)
Change in unrealized gains (losses)	(2,385,000)	124,000	(4,032,000)	(1,985,000)
Balance at end of year	(37,759,000)	(29,806,000)	(37,759,000)	(29,806,000)
Accumulated deferred gains (losses) on cash flow hedges:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	1,739,000	(263,000)	161,000	14,000
Translation (loss) gain during period	294,000	(381,000)	1,895,000	(644,000)
Settlement of cash flow hedge	143,000	0	166,000	14,000
Change in unrealized gains (losses)	294,000	(381,000)	1,895,000	(644,000)
Net change in cash flow hedges, net of taxes of $36, $127, $531, and $215	151,000	(381,000)	1,729,000	(658,000)
Amortization of actuarial losses, net of taxes	(143,000)	0	(166,000)	(14,000)
Balance at end of year	1,890,000	(644,000)	1,890,000	(644,000)
Income tax expense (benefit)	36,000	127,000	531,000	215,000
Accumulated effect of retirement benefit obligations:
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	(1,025,000)	(1,483,000)	(1,050,000)	(1,518,000)
Settlement of cash flow hedge	(13,000)	(19,000)	(38,000)	(54,000)
Amortization of actuarial losses, net of taxes	13,000	19,000	38,000	54,000
Balance at end of year	(1,012,000)	(1,464,000)	(1,012,000)	(1,464,000)
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of year	(34,660,000)	(31,676,000)	(34,616,000)	(29,325,000)
Balance at end of year	$ (36,881,000)	$ (31,914,000)	$ (36,881,000)	$ (31,914,000)