Intangible Assets (Details 1) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	$ 60,038	$ 59,507
Accumulated amortization	(31,169)	(24,512)
Net book value	28,869	34,995
Aggregate amortization expense	6,657	6,703
Deferred financing costs [Member]
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	6,427	6,427
Accumulated amortization	(4,048)	(3,399)
Net book value	2,379	3,028
Customer relationships [Member]
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	38,427	38,170
Accumulated amortization	(18,703)	(14,684)
Net book value	19,724	23,486
Technology [Member]
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	12,092	11,880
Accumulated amortization	(6,538)	(5,074)
Net book value	5,554	6,806
License [Member]
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	2,480	2,480
Accumulated amortization	(1,340)	(850)
Net book value	1,140	1,630
Non-compete contracts [Member]
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	550	550
Accumulated amortization	(530)	(505)
Net book value	20	45
Trade name [Member]
Summary of cost, accumulated amortization and net book value of intangible assets
Cost	62	0
Accumulated amortization	(10)	0
Net book value	$ 52	$ 0