Derivative Financial Instruments (Details Textuals) In Millions	6 Months Ended
Jun. 30, 2011 USD ($)	Jun. 30, 2010 USD ($)	Jun. 30, 2011 NOK	Jun. 30, 2011 GBP (£)	Jun. 30, 2011 AUD	Jun. 30, 2011 BRL
Foreign Currency Accounting Hedges
Notional amount of foreign currency contracts settled	$ 145.5	$ 147.2
Notional amount of foreign currency contracts not designated as accounting hedges settled	0	0
FOREX contracts outstanding in the aggregate notional amount	122.4		1.7	17.4	36.9	66.4
Reclassification unrealized gains associated with FOREX contracts	$ 8.4

The estimated net amount of unrealized gains or losses on foreign currency cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-Subparagraph b(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6887037&loc=d3e80748-113994

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