Current report of foreign issuer pursuant to Rules 13a-16 and 15d-16 Amendments

Goodwill and Other Intangible Assets (Schedule of Other Intangible Assets) (Details)

v3.19.1
Goodwill and Other Intangible Assets (Schedule of Other Intangible Assets) (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount $ 458,262 $ 457,963
Accumulated Amortization (356,776) (350,689)
Net Book Value 101,486 107,274
Developed technology [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 299,100 299,100
Accumulated Amortization (240,316) (236,375)
Net Book Value 58,784 62,725
Patents [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 10,483 10,127
Accumulated Amortization (5,960) (5,752)
Net Book Value 4,523 4,375
Trademarks and trade names [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 26,224 26,212
Accumulated Amortization (20,404) (19,067)
Net Book Value 5,820 7,145
Customer relationships [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 102,914 102,984
Accumulated Amortization (70,868) (70,353)
Net Book Value 32,046 32,631
Capitalized software development costs [Member]    
Finite-Lived Intangible Assets [Line Items]    
Gross Carrying Amount 19,541 19,540
Accumulated Amortization (19,228) (19,142)
Net Book Value $ 313 $ 398