Goodwill and Intangible Assets Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Translation Adjustments	$ 100	$ 100
Finite-Lived Intangible Assets, Gross	45,746	44,654
Finite-Lived Intangible Assets, Accumulated Amortization	37,405	30,049
Finite-Lived Intangible Assets, Net	8,341	14,605
Amortization of Intangible Assets	$ 6,300	$ 6,800	$ 7,600
Developed Technology Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	7 years	7 years
Finite-Lived Intangible Assets, Gross	$ 27,700	$ 26,839
Finite-Lived Intangible Assets, Accumulated Amortization	22,077	17,653
Finite-Lived Intangible Assets, Net	$ 5,623	$ 9,186
Maintenance relationship [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	8 years	8 years
Finite-Lived Intangible Assets, Gross	$ 3,608	$ 3,451
Finite-Lived Intangible Assets, Accumulated Amortization	3,259	2,790
Finite-Lived Intangible Assets, Net	$ 349	$ 661
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	6 years	6 years
Finite-Lived Intangible Assets, Gross	$ 12,513	$ 12,439
Finite-Lived Intangible Assets, Accumulated Amortization	10,144	8,478
Finite-Lived Intangible Assets, Net	$ 2,369	$ 3,961
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	2 years	2 years
Finite-Lived Intangible Assets, Gross	$ 1,925	$ 1,925
Finite-Lived Intangible Assets, Accumulated Amortization	1,925	1,128
Finite-Lived Intangible Assets, Net	$ 0	$ 797