Accumulated Other Comprehensive Income (Loss) (Schedule of Accumulated Other Comprehensive Income (Loss) (Details)) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		$ (114,386)	$ (193,798)
Accumulated Other Comprehensive Income (Loss), Debt Securities, Available-for-sale, Adjustment, after Tax		0	3,411	$ 0
Foreign currency translation adjustment		(41,716)	76,023	(45,426)
Amounts reclassified from accumulated other comprehensive loss		(356)	(35)	22
Unrealized gain on available for sale securities		0	5,398	0
Other Comprehensive Income (Loss), before Reclassifications, before Tax		(42,072)	81,986
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net		(370)
Net current-period other comprehensive (loss) income, before income taxes		(42,442)	81,386	(45,404)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Tax			5,398
Income tax expense		45	(1,974)	(12,337)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Tax			(1,987)
Net current-period other comprehensive (loss) income, net of income taxes		(42,397)	79,412	(57,741)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax			3,411
Cumulative effects of adoption of accounting standards		12,619
Ending Balance		(160,194)	(114,386)	(193,798)
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	[1]	0	(600)
Cash Flow Hedging [Member] | Interest Rate Swap [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive loss		(356)	565
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		(118,166)	(194,189)
Foreign currency translation adjustment			76,023
Net current-period other comprehensive (loss) income, before income taxes		(41,716)	76,023
Income tax expense		(38)
Net current-period other comprehensive (loss) income, net of income taxes		(41,754)	76,023
Ending Balance		(159,920)	(118,166)	(194,189)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance		369	391
Net current-period other comprehensive (loss) income, before income taxes		(726)	(35)
Income tax expense		83	13
Net current-period other comprehensive (loss) income, net of income taxes		(643)	(22)
Ending Balance		(274)	369	391
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net current-period other comprehensive (loss) income, net of income taxes		(42,397)	$ 79,412	$ (57,741)
Cumulative effects of adoption of accounting standards		$ (3,411)

[1] There were no gains or losses recognized in earnings related to any ineffective portion of the hedging relationship or related to any amount excluded from the assessment of hedge effectiveness for the years ended December 31, 2018 and 2017.