Goodwill and Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Goodwill, Cost:
Beginning balance	$ 253,834	$ 256,192	$ 248,911		$ 248,911
Acquisitons	272		266
Additional purchase accounting adjustments	(99)	(50)	5,183
Foreign currency translation	2,584	(2,308)	1,832
Ending balance	256,591	253,834	256,192		256,591		248,911
Goodwill, Accumulated impairment:
Beginning balance	(43,760)	(44,645)	(43,546)		(43,546)
Foreign currency translation	(1,215)	885	(1,099)
Ending balance	(44,975)	(43,760)	(44,645)		(44,975)		(43,546)
Goodwill, Net book value:
Beginning balance	210,074	211,547	205,365		205,365
Ending balance	211,616	210,074	211,547		211,616		205,365
Impairment charges of long-lived assets	4,281			0	4,281	0
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					12 years 10 months 24 days		12 years 4 months 24 days
Cost	63,038				63,038		69,450
Accumulated Amortization	(31,857)				(31,857)		(27,387)
Net	31,181				31,181		42,063
Period over which acquired companies have had key relationships with fortune 500 companies, minimum					15 years
Amortization expense related to other intangible assets	1,349			1,231	4,125	3,704
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
Future amortization expense, 2013	4,161				4,161
Future amortization expense, 2014	4,156				4,156
Future amortization expense, 2015	4,030				4,030
Future amortization expense, 2016	3,963				3,963
Future amortization expense, 2017	3,786				3,786
Customer relationships [Member]
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					13 years 8 months 12 days		12 years 10 months 24 days
Cost	58,297				58,297		65,466
Accumulated Amortization	(27,795)				(27,795)		(23,757)
Net	30,502				30,502		41,709
Digital images [Member]
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					5 years		5 years
Cost	450				450		450
Accumulated Amortization	(450)				(450)		(450)
Net	0				0		0
Developed technologies [Member]
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					3 years		3 years
Cost	712				712		712
Accumulated Amortization	(712)				(712)		(712)
Net	0				0		0
Non-compete agreements [Member]
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					3 years 6 months		3 years 7 months 6 days
Cost	883				883		864
Accumulated Amortization	(821)				(821)		(774)
Net	62				62		90
Trade names [Member]
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					3 years 10 months 24 days		2 years 9 months 18 days
Cost	1,476				1,476		738
Accumulated Amortization	(859)				(859)		(707)
Net	617				617		31
Contract acquisition cost [Member]
Other intangible assets subject to amortization [Abstract]
Weighted Average Life					3 years		3 years
Cost	1,220				1,220		1,220
Accumulated Amortization	(1,220)				(1,220)		(987)
Net	0				0		233
Americas [Member]
Goodwill, Cost:
Beginning balance	202,178	202,778	198,510		198,510
Acquisitons	272		266
Additional purchase accounting adjustments	(99)	0	3,507
Foreign currency translation	911	(600)	495
Ending balance	203,262	202,178	202,778		203,262
Goodwill, Accumulated impairment:
Beginning balance	(14,397)	(14,538)	(14,422)		(14,422)
Foreign currency translation	(214)	141	(116)
Ending balance	(14,611)	(14,397)	(14,538)		(14,611)
Goodwill, Net book value:
Beginning balance	187,781	188,240	184,088		184,088
Ending balance	188,651	187,781	188,240		188,651
Impairment charges of long-lived assets	2,350
Europe [Member]
Goodwill, Cost:
Beginning balance	41,013	42,406	40,364		40,364
Acquisitons	0		0
Additional purchase accounting adjustments	0	(50)	992
Foreign currency translation	1,317	(1,343)	1,050
Ending balance	42,330	41,013	42,406		42,330
Goodwill, Accumulated impairment:
Beginning balance	(28,119)	(28,835)	(27,878)		(27,878)
Foreign currency translation	(974)	716	(957)
Ending balance	(29,093)	(28,119)	(28,835)		(29,093)
Goodwill, Net book value:
Beginning balance	12,894	13,571	12,486		12,486
Ending balance	13,237	12,894	13,571		13,237
Impairment charges of long-lived assets	1,413
Asia Pacific [Member]
Goodwill, Cost:
Beginning balance	10,643	11,008	10,037		10,037
Acquisitons	0		0
Additional purchase accounting adjustments	0	0	683
Foreign currency translation	356	(365)	288
Ending balance	10,999	10,643	11,008		10,999
Goodwill, Accumulated impairment:
Beginning balance	(1,244)	(1,272)	(1,246)		(1,246)
Foreign currency translation	(27)	28	(26)
Ending balance	(1,271)	(1,244)	(1,272)		(1,271)
Goodwill, Net book value:
Beginning balance	9,399	9,736	8,791		8,791
Ending balance	$ 9,728	$ 9,399	$ 9,736		$ 9,728