Derivative Instruments (Location and Amounts of Derivative Fair Values On The Condensed Consolidated Balance Sheets) (Details) (Derivatives not designated as hedging instruments [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Asset Derivative Notional Amount	$ 307,191	$ 132,864
Asset Derivative Fair Value	9,248	2,245
Liability Derivative Notional Amount	204,906	194,566
Liability Derivative Fair Value	4,773	2,656
Put options [Member] | Equity securities trading, at fair value [Member]
Derivatives, Fair Value [Line Items]
Asset Derivative Notional Amount	0	5,152
Asset Derivative Fair Value	0	532
Liability Derivative Notional Amount	0	0
Liability Derivative Fair Value	0	0
Foreign exchange contracts | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivative Notional Amount	307,191	127,712
Asset Derivative Fair Value	9,248	1,713
Foreign exchange contracts | Accounts payable and accrued liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivative Notional Amount	171,906	194,566
Liability Derivative Fair Value	4,612	2,656
Interest rate swaps | Other assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivative Notional Amount	0	0
Asset Derivative Fair Value	0	0
Interest rate swaps | Accounts payable and accrued liabilities [Member]
Derivatives, Fair Value [Line Items]
Liability Derivative Notional Amount	33,000	0
Liability Derivative Fair Value	$ 161	$ 0