Goodwill and Intangible Assets (Schedule of Gross Carrying Value and Accumulated Amortization for Each Major Class of Intangible Asset) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	$ 401,846	$ 414,254
Intangible assets - Gross Carrying Amount	463,946	476,354
Amortized intangible assets - Accumulated Amortization	(206,487)	(205,190)
Amortized intangible assets - Net	195,359us-gaap_FiniteLivedIntangibleAssetsNet	209,064us-gaap_FiniteLivedIntangibleAssetsNet
Intangible assets - Net	257,459	271,164
Patents
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	10,062	10,016
Amortized intangible assets - Accumulated Amortization	(5,541)	(5,313)
Amortized intangible assets - Net	4,521	4,703
Amortized intangible assets - Weighted Average Life	11 years
Trade names
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	102,228	104,118
Amortized intangible assets - Accumulated Amortization	(33,778)	(32,881)
Amortized intangible assets - Net	68,450	71,237
Amortized intangible assets - Weighted Average Life	16 years
Customer relationships
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	213,427	222,486
Amortized intangible assets - Accumulated Amortization	(124,939)	(126,193)
Amortized intangible assets - Net	88,488	96,293
Amortized intangible assets - Weighted Average Life	11 years
Non-compete agreements
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	793	840
Amortized intangible assets - Accumulated Amortization	(661)	(636)
Amortized intangible assets - Net	132	204
Amortized intangible assets - Weighted Average Life	3 years
Unpatented technology
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	68,309	69,760
Amortized intangible assets - Accumulated Amortization	(36,392)	(35,165)
Amortized intangible assets - Net	31,917	34,595
Amortized intangible assets - Weighted Average Life	11 years
Other
Goodwill And Intangible Assets [Line Items]
Amortized intangible assets - Gross Carrying Amount	7,027	7,034
Amortized intangible assets - Accumulated Amortization	(5,176)	(5,002)
Amortized intangible assets - Net	1,851	2,032
Amortized intangible assets - Weighted Average Life	10 years
Banjo trade name
Goodwill And Intangible Assets [Line Items]
Indefinite lived intangible assets - Gross Carrying Amount	62,100	62,100
Indefinite lived intangible assets - Net	$ 62,100	$ 62,100

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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