Accumulated Other Comprehensive Income (Schedule Of Accumulated Other Comprehensive Income) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($)
Balance, value	$ (108,213)
Balance, value	(48,391)
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Balance, value	(43,053)
Other comprehensive income (loss) before reclassifications	8,992
Gains reclassified from accumulated other comprehensive income	(587)
Balance, value	(34,648)
Unrealized Gain on Investments, Net of Tax [Member]
Balance, value	20
Other comprehensive income (loss) before reclassifications	109
Balance, value	129
Unrealized Gain (Loss) on Derivative Instruments, Net of Tax [Member]
Balance, value	4,916
Other comprehensive income (loss) before reclassifications	(8,472)
Gains reclassified from accumulated other comprehensive income	(587)
Balance, value	(4,143)
Unrealized Gain (Loss) on Net Investment Hedge, Net of Tax [Member]
Balance, value	4,036
Other comprehensive income (loss) before reclassifications	(6,895)
Balance, value	(2,859)
Cumulative Translation Adjustment [Member]
Balance, value	(52,025)
Other comprehensive income (loss) before reclassifications	24,250
Balance, value	$ (27,775)

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 55
-Paragraph 4I
-URI http://asc.fasb.org/extlink&oid=84234705&loc=SL4590271-111686

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4568740-111683

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4568447-111683

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