Intangible Assets Schedule of Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2016

Schedule of Intangible Assets [Abstract]

Schedule of Finite-Lived Intangible Assets [Table Text Block]

The gross carrying amount and accumulated amortization of our intangible assets, other than goodwill, are as follows:

	December 31, 2016							December 31, 2015
	Gross Assets		Accumulated Amortization			Net		Gross Assets		Accumulated Amortization			Net
	(in thousands)
Core-developed technology	$	372,568	$	(354,878	)	$	17,690	$	388,981	$	(358,092	)	$	30,889
Customer contracts and relationships	224,467		(170,056		)	54,411		238,379		(168,885		)	69,494
Trademarks and trade names	61,785		(61,766		)	19		64,069		(62,571		)	1,498
Other	11,076		(11,045		)	31		11,078		(11,027		)	51
Total intangible assets	$	669,896	$	(597,745	)	$	72,151	$	702,507	$	(600,575	)	$	101,932

SummaryOfIntangibleAssetAccountActivity [Table Text Block]

A summary of the intangible asset account activity is as follows:

	Year Ended December 31,
	2016			2015
	(in thousands)
Beginning balance, intangible assets, gross	$	702,507		$	748,148
Intangible assets acquired	—			4,827
Intangible assets impaired	—			(497		)
Effect of change in exchange rates	(32,611		)	(49,971		)
Ending balance, intangible assets, gross	$	669,896		$	702,507

Finite-lived Intangible Assets Amortization Expense [Table Text Block]

A summary of intangible asset amortization expense is as follows:

	Year Ended December 31,
	2016		2015		2014
	(in thousands)
Amortization expense	$	25,112	$	31,673	$	43,619

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

Estimated future annual amortization expense is as follows:

Year Ending December 31,	Estimated Annual Amortization
	(in thousands)
2017	$	17,914
2018	12,383
2019	9,695
2020	7,866
2021	6,845
Beyond 2021	17,448
Total intangible assets subject to amortization	$	72,151