Goodwill and Intangible Assets, Net (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Changes in the carrying amount of goodwill
Balance at the beginning of the period			$ 121,981
Acquisitions			2,606
Reclassifications			5,253
Foreign exchange			430
Balance at the end of the period	130,270	128,812	130,270	128,812
Changes in the carrying amount of intangible assets
Balance at the beginning of the period			50,598
Acquisitions			1,869
Reclassifications			(10,318)
Amortization	(1,200)	(1,700)	(5,209)	(5,400)
Foreign exchange			15
Balance at the end of the period	$ 36,955	$ 40,075	$ 36,955	$ 40,075