SEGMENT REPORTING (Schedule of Financial Data by Reporting Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Statements of operations:
Net revenues	$ 125,771	$ 125,892	$ 127,015	$ 126,603	$ 118,735	$ 119,184	$ 118,990	$ 116,925	$ 505,281	$ 473,834	$ 441,753
Depreciation									32,482	30,831	25,980
Amortization									3,981	6,365	7,386
Asset impairments									879	456	290
Interest expense									(7,167)	(9,954)	(10,785)
Interest income									49	46	157
Income tax expense (benefit)									5,445	8,586	1,540
Operating income	10,253	8,690	11,395	11,088	9,978	9,911	9,028	7,039	41,426	35,956	20,981
Balance sheets:
Intangibles, net of amortization	7,384				10,906				7,384	10,906	16,967
Property and equipment, net	104,613				103,449				104,613	103,449	107,238
Assets	545,803				542,821				545,803	542,821	541,657
Expenditures for long-lived assets:
Capital expenditures									32,338	30,100	32,868
Business dispositions										1,902	51,281
North America [Member]
Statements of operations:
Net revenues									336,836	316,231	303,906
Depreciation									26,901	25,933	22,040
Amortization									2,716	4,465	5,552
Asset impairments									861	440	175
Interest expense									(7,091)	(9,860)	(10,735)
Interest income									24	1	89
Income tax expense (benefit)									(209)	8,340	(4,186)
Operating income									9,853	1,849	(4,369)
Balance sheets:
Intangibles, net of amortization	7,384				9,633				7,384	9,633	13,823
Property and equipment, net	86,396				87,745				86,396	87,745	93,158
Assets	455,345				454,738				455,345	454,738	451,690
Expenditures for long-lived assets:
Capital expenditures									23,843	24,304	28,862
Business dispositions										1,902	45,174
Europe [Member]
Statements of operations:
Net revenues									105,488	97,986	85,342
Depreciation									3,369	2,949	2,375
Amortization									1,265	1,640	1,560
Asset impairments									18	16	115
Interest expense									(248)	44	113
Interest income									19	28	46
Income tax expense (benefit)									5,206	3,121	1,504
Operating income									27,279	26,739	20,318
Balance sheets:
Intangibles, net of amortization					1,273					1,273	2,888
Property and equipment, net	12,208				10,041				12,208	10,041	9,413
Assets	59,283				55,826				59,283	55,826	56,135
Expenditures for long-lived assets:
Capital expenditures									5,802	2,846	2,629
Business dispositions											6,107
Asia Pacific [Member]
Statements of operations:
Net revenues									62,957	59,617	52,505
Depreciation									2,212	1,949	1,565
Amortization										260	274
Asset impairments
Interest expense									172	(138)	(163)
Interest income									6	17	22
Income tax expense (benefit)									448	(2,875)	4,222
Operating income									4,294	7,368	5,032
Balance sheets:
Intangibles, net of amortization											256
Property and equipment, net	6,009				5,663				6,009	5,663	4,667
Assets	31,175				32,257				31,175	32,257	33,832
Expenditures for long-lived assets:
Capital expenditures									2,693	2,950	1,377
Business dispositions