Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Amortization expense		$ 35,124	$ 61,066	$ 39,484
Annual amortization expense in 2017		33,286
Annual amortization expense in 2018		28,287
Annual amortization expense in 2019		19,883
Annual amortization expense in 2020		16,121
Annual amortization expense in 2021		11,865
Impairment of Intangible Assets, Finite-lived	$ 93,520	$ 0	93,520	$ 0
Acquired Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			19,164
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			63,852
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			5,952
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			3,416
Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			791
Internally Developed Software [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			345
Americas [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			92,248
Other EMEA [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			$ 1,272