Acquisitions - Intangible Assets Related to Acquisition (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended	0 Months Ended
	Dec. 31, 2014	Jun. 11, 2014	Mar. 31, 2014	Dec. 10, 2012	Jul. 27, 2012	Dec. 31, 2013	Dec. 31, 2012
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Goodwill	943,374					$ 773,048	$ 778,708
Developed Technologies [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Weighted average amortization period	4 years 8 months 12 days
Customer Relationships [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Weighted average amortization period	19 years 7 months 6 days
Trademarks [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Weighted average amortization period	5 years
Prosoft Technology, Inc. [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization		40,800
Goodwill		56,193
Intangible assets not subject to amortization		56,193
Total intangible assets		96,993
Weighted average amortization period		14 years 9 months 18 days
Prosoft Technology, Inc. [Member] | Developed Technologies [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization		9,000
Weighted average amortization period		5 years
Prosoft Technology, Inc. [Member] | Customer Relationships [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization		26,600
Weighted average amortization period		20 years
Prosoft Technology, Inc. [Member] | Backlog [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization		200
Weighted average amortization period		3 months 18 days
Prosoft Technology, Inc. [Member] | Trademarks [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization		5,000
Weighted average amortization period		5 years
Grass Valley [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization			65,500
Goodwill			119,589
Intangible assets not subject to amortization			149,589
Total intangible assets			215,089
Weighted average amortization period			9 years
Grass Valley [Member] | In-Process/Service Research and Development [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization			8,000
Grass Valley [Member] | Trademarks [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization			22,000
Grass Valley [Member] | Developed Technologies [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization			37,000
Weighted average amortization period			5 years
Grass Valley [Member] | Customer Relationships [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization			27,000
Weighted average amortization period			15 years
Grass Valley [Member] | Backlog [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization			1,500
Weighted average amortization period			3 months 18 days
PPC Broadband, Inc. [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization				132,500
Goodwill				277,091
Intangible assets not subject to amortization				309,091
Total intangible assets				441,591
Weighted average amortization period				11 years 2 months 12 days
PPC Broadband, Inc. [Member] | In-Process/Service Research and Development [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization				5,000
PPC Broadband, Inc. [Member] | Trademarks [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization				27,000
PPC Broadband, Inc. [Member] | Developed Technologies [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization				76,000
Weighted average amortization period				5 years
PPC Broadband, Inc. [Member] | Customer Relationships [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization				55,000
Weighted average amortization period				20 years
PPC Broadband, Inc. [Member] | Backlog [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization				1,500
Weighted average amortization period				6 months
Miranda Technologies Inc. [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization					117,524
Goodwill					161,206
Intangible assets not subject to amortization					203,673
Total intangible assets					321,197
Weighted average amortization period					9 years 10 months 24 days
Miranda Technologies Inc. [Member] | In-Process/Service Research and Development [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization					6,913
Miranda Technologies Inc. [Member] | Trademarks [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization					35,554
Miranda Technologies Inc. [Member] | Developed Technologies [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization					69,132
Weighted average amortization period					4 years
Miranda Technologies Inc. [Member] | Customer Relationships [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization					44,442
Weighted average amortization period					20 years
Miranda Technologies Inc. [Member] | Backlog [Member]
Acquired Finite And Indefinite Lived Intangible Assets [Line Items]
Intangible assets subject to amortization					$ 3,950
Weighted average amortization period					1 year