Intangible Assets and Debt Issuance Costs (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	$ 173,762	$ 121,217
Amortized Intangible Assets, Accumulated Amortization	(106,708)	(99,464)
Amortized Intangible Assets, Net Amount	67,054	21,753
Unamortized Intangible Assets (Trademarks), Weighted Useful Lives	0
Trademarks, net	2,308	2,308
Intangible assets, gross carrying amount	180,294	127,203
Intangible assets, accumulated amortization	(109,317)	(101,056)
Intangible assets, net amount	70,977	26,147
Licenses
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	4 years 11 months 16 days
Amortized Intangible Assets, Gross Carrying Amount	91,488	91,488
Amortized Intangible Assets, Accumulated Amortization	(77,844)	(72,797)
Amortized Intangible Assets, Net Amount	13,644	18,691
Product lines
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	3 years 7 months 24 days
Amortized Intangible Assets, Gross Carrying Amount	66,594	19,500
Amortized Intangible Assets, Accumulated Amortization	(19,561)	(18,787)
Amortized Intangible Assets, Net Amount	47,033	713
Customer relationships
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	5 years 3 months 11 days
Amortized Intangible Assets, Gross Carrying Amount	9,347	7,096
Amortized Intangible Assets, Accumulated Amortization	(5,903)	(4,800)
Amortized Intangible Assets, Net Amount	3,444	2,296
Trade Name
Acquired Intangible Assets by Major Class [Line Items]
Amortized Intangible Assets, Gross Carrying Amount	3,000
Amortized Intangible Assets, Accumulated Amortization	(250)
Amortized Intangible Assets, Net Amount	2,750
Non-compete/Employment contracts
Acquired Intangible Assets by Major Class [Line Items]
Weighted Useful Lives (Years)	3 years 10 months 2 days
Amortized Intangible Assets, Gross Carrying Amount	3,333	3,133
Amortized Intangible Assets, Accumulated Amortization	(3,150)	(3,080)
Amortized Intangible Assets, Net Amount	183	53
4.50% Convertible senior notes
Acquired Intangible Assets by Major Class [Line Items]
Deferred Costs, Gross Carrying Amount	4,224	3,678
Deferred Costs, Weighted Useful Lives (Years)	5 years
Deferred Costs, Accumulated Amortization	(2,609)	(1,592)
Deferred Costs, Net Amount	$ 1,615	$ 2,086