Accumulated Other Comprehensive Income (Schedule Of Accumulated Other Comprehensive Income) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Balance, value	$ (53,842)
Balance, value	(48,982)
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Balance, value	(36,470)
Other comprehensive income (loss) before reclassifications	679
Gains reclassified from accumulated other comprehensive income	1,585
Balance, value	(34,206)
Unrealized (Loss) Gain on Investments, Net of Tax [Member]
Balance, value	(22)
Other comprehensive income (loss) before reclassifications	118
Balance, value	96
Unrealized (Loss) Gain on Derivative Instruments, Net of Tax [Member]
Balance, value	(5,219)
Other comprehensive income (loss) before reclassifications	(2,388)
Gains reclassified from accumulated other comprehensive income	1,585
Balance, value	(6,022)
Unrealized Loss on Net Investment Hedge, Net of Tax [Member]
Balance, value	(4,311)
Other comprehensive income (loss) before reclassifications	(2,216)
Balance, value	(6,527)
Cumulative Translation Adjustment [Member]
Balance, value	(26,918)
Other comprehensive income (loss) before reclassifications	5,165
Balance, value	$ (21,753)

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

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