Acquisitions - Summery of Purchase Price Allocation to Identifiable Intangible Assets (Detail) (Johnson City And Morristown Territory Acquisition [Member], USD $) In Thousands, unless otherwise specified	0 Months Ended
	May 23, 2014	May 23, 2014
Schedule Of Intangible Assets [Line Items]
Additions to other identifiable intangible related to acquisition	$ 13,800	$ 13,800
Distribution agreements [Member]
Schedule Of Intangible Assets [Line Items]
Additions to other identifiable intangible related to acquisition		13,200
Estimated useful life	40 years
Customer lists [Member]
Schedule Of Intangible Assets [Line Items]
Additions to other identifiable intangible related to acquisition		$ 600
Estimated useful life	12 years