Allocation of Purchase Price for Acquisitions and Enterprise Value of Channel Intelligence (Parenthetical) (Detail)	6 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2013
Customer Lists | Superior Access | Minimum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	5 years
Customer Lists | Superior Access | Maximum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	11 years
Trademarks, trade names and domain names | Superior Access | Minimum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	5 years
Trademarks, trade names and domain names | Superior Access | Maximum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	11 years
Technology | Minimum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	5 years	5 years
Technology | Maximum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	10 years	10 years
Technology | Superior Access
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	5 years
Non-compete agreements | Minimum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	2 years	2 years
Non-compete agreements | Maximum
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	5 years	5 years
Non-compete agreements | Superior Access
Schedule Of Business Acquisitions Purchase Price Allocation [Line Items]
Finite intangible assets, useful life	3 years