Accumulated Other Comprehensive Income (Schedule of Reclassifications out of Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Tax expense (benefits)	$ 21,535	$ 25,072	$ 66,392	$ 75,036
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(893)	648	935	1,117
Tax expense (benefits)	(333)	197	348	313
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(560)	451	587	804
Foreign Currency Exchange Contracts [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	$ (893)	$ 648	$ 935	1,538
Interest Rate Swaps [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax				$ (421)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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

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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
-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

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