Derivative Financial Instruments (Narrativel) (Details) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Total gross notional amount related to foreign currency forward contracts	$ 206,900
Net cash inflows/(outflows) on the settlement of derivatives	1,461	(5,839)
Aggregate notional amount of the receive-variable/pay-fixed interest rate swaps at end of period	$ 71,800
Derivative, Lower Remaining Maturity Range	2011
Derivative, Higher Remaining Maturity Range	2013

Amount of net cash inflows/(outflows) in the period from the settlement of derivatives included within the "net change in contracts in process and billings in excess of costs and estimated earnings on uncompleted contracts" in the consolidated statement of cash flows.

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- Definition

The high end of the range of time remaining until maturity when a range is presented for a group of derivatives.

+ Details

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- Details

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- Definition

The low end of the range of time remaining until maturity when a range is presented for a group of derivatives.

+ Details

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- Definition

Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

+ Details

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Balance Type:	debit
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- Definition

Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5579245-113959

+ Details

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