Identifiable Intangible Assets - (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets and Goodwill [Line Items]
Goodwill	$ 22,495		$ 22,553	$ 15,361
Goodwill, Acquired During Period	0		6,989
Goodwill, Translation and Purchase Accounting Adjustments			203
Business Acquisition Purchase Price Allocation Goodwill Amount 2		(58)
Finite-Lived Intangible Assets, Gross	73,752		73,752
Finite-Lived Intangible Assets, Accumulated Amortization	62,958		62,288
Intangible Assets, Net (Excluding Goodwill)	10,794		11,464
Amortization of Intangible Assets	670	616
Future Amortization Expense, Remainder of Fiscal Year	1,752
Future Amortization Expense, Year One	2,050
Future Amortization Expense, Year Two	1,941
Future Amortization Expense, Year Three	1,553
Future Amortization Expense, Year Four	1,117
Future Amortization Expense, Year Five	1,117
Developed Technology Rights [Member]
Finite-Lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	59,831		59,831
Finite-Lived Intangible Assets, Accumulated Amortization	52,032		51,496
Intangible Assets, Net (Excluding Goodwill)	7,799		8,335
Customer Relationships [Member]
Finite-Lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	9,560		9,560
Finite-Lived Intangible Assets, Accumulated Amortization	7,544		7,449
Intangible Assets, Net (Excluding Goodwill)	2,016		2,111
Trade Names [Member]
Finite-Lived Intangible Assets and Goodwill [Line Items]
Finite-Lived Intangible Assets, Gross	4,361		4,361
Finite-Lived Intangible Assets, Accumulated Amortization	3,382		3,343
Intangible Assets, Net (Excluding Goodwill)	$ 979		$ 1,018