Goodwill and Intangible Assets - Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Intangible assets
Gross Carrying Amount	$ 150,115	$ 50,614
Accumulated Amortization	47,665	25,930
Customer contracts
Intangible assets
Gross Carrying Amount	25,373	243
Accumulated Amortization	$ 8,634	71
Customer contracts | Minimum
Intangible assets
Useful Life in Years	1 year
Customer contracts | Maximum
Intangible assets
Useful Life in Years	4 years
Customer relationships
Intangible assets
Gross Carrying Amount	$ 84,971	42,345
Accumulated Amortization	$ 27,585	21,228
Customer relationships | Minimum
Intangible assets
Useful Life in Years	3 years
Customer relationships | Maximum
Intangible assets
Useful Life in Years	13 years
Non-competition agreements
Intangible assets
Gross Carrying Amount	$ 3,700	3,495
Accumulated Amortization	$ 1,728	1,072
Non-competition agreements | Minimum
Intangible assets
Useful Life in Years	2 years
Non-competition agreements | Maximum
Intangible assets
Useful Life in Years	5 years
Trade names
Intangible assets
Gross Carrying Amount	$ 22,920	160
Accumulated Amortization	$ 3,906	67
Trade names | Minimum
Intangible assets
Useful Life in Years	5 years
Trade names | Maximum
Intangible assets
Useful Life in Years	8 years
Technology and software
Intangible assets
Gross Carrying Amount	$ 9,851	4,321
Accumulated Amortization	$ 5,124	3,461
Technology and software | Minimum
Intangible assets
Useful Life in Years	3 years
Technology and software | Maximum
Intangible assets
Useful Life in Years	7 years
Publishing content
Intangible assets
Useful Life in Years	3 years
Gross Carrying Amount	$ 3,300
Accumulated Amortization	$ 688
License
Intangible assets
Useful Life in Years	2 years
Gross Carrying Amount		50
Accumulated Amortization		$ 31