Accumulated Other Comprehensive Income (Loss) (Schedule of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (193,798)	$ (136,057)
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	0
Foreign currency translation adjustment	9,864	15,385
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax	4,021
Other comprehensive income before reclassifications	14,206	13,644
Amounts reclassified from accumulated other comprehensive loss	(2)	163
Net current-period other comprehensive income, before income taxes	14,204	13,807
Income tax expense	(1,597)	(1,899)
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax	(1,480)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	12,607	11,908
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	2,541
Accumulated Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	2,541
Ending balance	(181,191)	(124,149)
Cash Flow Hedging [Member] | Interest Expense [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	(2)	163
Cash Flow Hedging [Member] | Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net	321	(1,741)
Accumulated Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(194,189)	(136,434)
Amounts reclassified from accumulated other comprehensive loss	0	0
Net current-period other comprehensive income, before income taxes	9,864	15,385
Income tax expense	0	(2,477)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	9,864	12,908
Ending balance	(184,325)	(123,526)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	391	377
Net current-period other comprehensive income, before income taxes	319	(1,578)
Income tax expense	(117)	578
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	202	(1,000)
Ending balance	$ 593	$ (623)