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Derivative Instruments And Hedging Strategies (Fair Values Of Derivative Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 01, 2015
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 1,237	$ 469
Derivative Liability	20,617	10,896
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Derivative Liability	389	0
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	1,237	469
Derivative Liability	20,228	10,896
Foreign Exchange [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Derivative Liability	316	0
Foreign Exchange [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	195	0
Derivative Liability	194	57
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Derivative Liability	73	0
Interest Rate Swap [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0	0
Derivative Liability	0	242
Equity Option [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0
Options On Equities And Equity Indices [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		0
Derivative Liability	0	4,005
Commodity Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	1,042	469
Derivative Liability	598	981
Three Point Seven Five Percentage Convertible Notes [Member]
Derivatives, Fair Value [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability			$ 8,500
Three Point Seven Five Percentage Convertible Notes [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Asset	0	0
Embedded Derivative, Fair Value of Embedded Derivative Liability	$ 19,436	$ 5,611