Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax assets (gross), beginning balance	$ 46,238	$ 30,221
Valuation allowance, beginning balance	(23,980)	(19,863)
Deferred tax asset (net), beginning balance	22,258	10,358
Net deferred income tax balance, beginning balance	20,057	7,493
Change recognized in profit or loss	10,024	15,748	$ 5,315
Change recognized in OCI	(27)	(23)
Change in consolidation scope	0	(3,120)
Other	0	0
Currency translation adjustments	(110)	(41)
Deferred tax assets (gross), ending balance	53,240	46,238	30,221
Valuation allowance, ending balance	(19,821)	(23,980)	(19,863)
Deferred tax asset (net), ending balance	33,419	22,258	10,358
Net deferred income tax balance, ending balance	29,944	20,057	7,493
Net operating loss carryforwards
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax assets (gross), beginning balance	28,423	23,468
Change recognized in profit or loss	(1,048)	(385)
Change recognized in OCI	0	0
Change in consolidation scope	0	5,889
Other	0	0
Currency translation adjustments	(912)	(549)
Deferred tax assets (gross), ending balance	26,463	28,423	23,468
Personnel-related accruals
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax assets (gross), beginning balance	7,302	2,538
Change recognized in profit or loss	257	5,414
Change recognized in OCI		0
Change in consolidation scope	0	9
Other	(30)	0
Currency translation adjustments	241	(659)
Deferred tax assets (gross), ending balance	7,770	7,302	2,538
Other accruals
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax assets (gross), beginning balance	3,093	2,285
Change recognized in profit or loss	975	1,353
Change recognized in OCI		0
Change in consolidation scope	0	0
Other	30	0
Currency translation adjustments	276	(545)
Deferred tax assets (gross), ending balance	4,374	3,093	2,285
Projected benefit obligation
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax assets (gross), beginning balance	578	472
Change recognized in profit or loss	213	202
Change recognized in OCI	466	(44)
Change in consolidation scope	0	0
Other	0	0
Currency translation adjustments	(50)	(52)
Deferred tax assets (gross), ending balance	1,207	578	472
Other
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax assets (gross), beginning balance	6,842	1,458
Change recognized in profit or loss	7,331	4,372
Change recognized in OCI	0	0
Change in consolidation scope	0	1,091
Other	(482)	0
Currency translation adjustments	(265)	(79)
Deferred tax assets (gross), ending balance	13,426	6,842	1,458
Deferred tax assets (gross)
Deferred Tax Asset and Liability Activity [Roll Forward]
Change recognized in profit or loss	7,728	10,956
Change recognized in OCI	466	(44)
Change in consolidation scope	0	6,989
Other	(482)	0
Currency translation adjustments	(710)	(1,884)
Valuation allowance
Deferred Tax Asset and Liability Activity [Roll Forward]
Change recognized in profit or loss	3,630	1,429
Change recognized in OCI	(16)	21
Change in consolidation scope	0	(7,177)
Other	0	0
Currency translation adjustments	545	1,610
Deferred tax asset (net)
Deferred Tax Asset and Liability Activity [Roll Forward]
Change recognized in profit or loss	11,358	12,385
Change recognized in OCI	450	(23)
Change in consolidation scope	0	(188)
Other	(482)	0
Currency translation adjustments	(165)	(274)
Intangible assets
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax liabilities, beginning balance	(150)	(2,861)
Change recognized in profit or loss	(6)	5,445
Change recognized in OCI	(477)	0
Change in consolidation scope	0	(2,979)
Other	(33)	0
Currency translation adjustments	35	245
Deferred tax liabilities, ending balance	(631)	(150)	(2,861)
Other
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax liabilities, beginning balance	(2,051)	(4)
Change recognized in profit or loss	(1,328)	(2,082)
Change recognized in OCI	0	0
Change in consolidation scope	0	47
Other	515	0
Currency translation adjustments	20	(12)
Deferred tax liabilities, ending balance	(2,844)	(2,051)	(4)
Deferred tax liabilities
Deferred Tax Asset and Liability Activity [Roll Forward]
Deferred tax liabilities, beginning balance	(2,201)	(2,865)
Change recognized in profit or loss	(1,334)	3,363
Change recognized in OCI	(477)	0
Change in consolidation scope	0	(2,932)
Other	482	0
Currency translation adjustments	55	233
Deferred tax liabilities, ending balance	$ (3,475)	$ (2,201)	$ (2,865)