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