Goodwill and Intangible Assets - Intangible Assets (Parenthetical) (Detail) (Granville-Phillips [Member], USD $) In Thousands, unless otherwise specified	0 Months Ended	9 Months Ended
	May 30, 2014	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets		$ 38,850
Acquired intangible assets	38,850
Completed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets		15,700
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	21,250	21,250
Trademarks and Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Acquired intangible assets	$ 1,900	$ 1,900