Business and Significant Accounting Policies (Detail) - Intangible Assets Subject to Amortization - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Finite-lived Intangible Assets [Roll Forward]
Gross cost	$ 54,258	$ 21,808
Additions due to acquisition	79,611	31,975
Intangibles fully amortized	(13,223)
Non-competition agreement		1,500
Foreign currency translation impact	(2,643)	(1,025)
Gross cost	118,003	54,258
Accumulated amortization	(21,459)	(23,569)
Finite-lived intangible assets, net	96,544	30,689
Trade Names
Finite-lived Intangible Assets [Roll Forward]
Gross cost	6,924	6,023
Additions due to acquisition	3,260	915
Intangibles fully amortized	(6,013)
Non-competition agreement		0
Foreign currency translation impact	(27)	(14)
Gross cost	4,144	6,924
Accumulated amortization	(681)	(6,202)
Finite-lived intangible assets, net	3,463	722
Customer Relationships
Finite-lived Intangible Assets [Roll Forward]
Gross cost	27,933	10,146
Additions due to acquisition	42,620	18,054
Intangibles fully amortized	(7,210)
Non-competition agreement		0
Foreign currency translation impact	(483)	(267)
Gross cost	62,860	27,933
Accumulated amortization	(9,028)	(11,072)
Finite-lived intangible assets, net	53,832	16,861
Content
Finite-lived Intangible Assets [Roll Forward]
Gross cost	3,560	3,496
Additions due to acquisition	2,000	206
Intangibles fully amortized	0
Non-competition agreement		0
Foreign currency translation impact	(110)	(142)
Gross cost	5,450	3,560
Accumulated amortization	(3,525)	(2,246)
Finite-lived intangible assets, net	1,925	1,314
Software
Finite-lived Intangible Assets [Roll Forward]
Gross cost	6,569	2,143
Additions due to acquisition	11,656	5,000
Intangibles fully amortized	0
Non-competition agreement		0
Foreign currency translation impact	(2,006)	(574)
Gross cost	16,219	6,569
Accumulated amortization	(3,699)	(2,603)
Finite-lived intangible assets, net	12,520	3,966
Non-Compete
Finite-lived Intangible Assets [Roll Forward]
Gross cost	9,272	0
Additions due to acquisition	20,075	7,800
Intangibles fully amortized	0
Non-competition agreement		1,500
Foreign currency translation impact	(17)	(28)
Gross cost	29,330	9,272
Accumulated amortization	(4,526)	(1,446)
Finite-lived intangible assets, net	$ 24,804	$ 7,826