Debt (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Fair value of debt	$ 689,699	$ 662,050
Borrowings under lines of credit and overdrafts	12,539	3,795
Total debt, net of unamortized discounts	670,690	646,613
Less current maturities	(66,320)	(4,494)
Long-term debt	604,370	642,119
Convertible Debt [Member] \| 3.375% Convertible Notes [Member]
Debt Instrument [Line Items]
Carrying amount of debt	55,636	55,636
Fair value of debt	61,240	57,977
Unamortized debt discount	(2,540)	(3,122)
Convertible notes stated interest rate	3.375%
Convertible notes balance	53,096
Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Carrying amount of debt	604,100	589,200
Fair value of debt	614,965	599,172
Line of credit facility, maximum borrowing capacity	750,000
Lines of Credit and Overdrafts [Member]
Debt Instrument [Line Items]
Fair value of debt	12,095	3,380
Borrowings under lines of credit and overdrafts	12,095	3,380
Foreign Bank Borrowings [Member]
Debt Instrument [Line Items]
Carrying amount of debt	810	945
Fair value of debt	812	947
Other Debt Obligations [Member]
Debt Instrument [Line Items]
Carrying amount of debt	589	574
Fair value of debt	587	574
Lines of Credit [Member]
Debt Instrument [Line Items]
Borrowings under lines of credit and overdrafts	11,200	2,800
Line of credit facility, maximum borrowing capacity	15,000
Line of credit, interest rate at period end	2.16%	2.16%
Repayment period	7 days
Bank Overdrafts [Member]
Debt Instrument [Line Items]
Borrowings under lines of credit and overdrafts	$ 895	$ 580
Repayment period	2 days
Minimum [Member]
Debt Instrument [Line Items]
Maturity of bank acceptances	3 months
Minimum [Member] \| Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Debt instrument basis spread on LIBOR	1.10%
Maximum [Member]
Debt Instrument [Line Items]
Maturity of bank acceptances	6 months
Maximum [Member] \| Revolving Credit Agreement [Member]
Debt Instrument [Line Items]
Debt instrument basis spread on LIBOR	1.70%

Long-term debt, gross, net of unamortized discounts

No definition available.

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- Definition

Maturity of Bank Acceptances

+ References

No definition available.

+ Details

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- Definition

Repayment period

+ References

No definition available.

+ Details

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- Definition

Total debt, net of unamortized discounts

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

The percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date before deducting unamortized discount or premiums (if any). May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

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-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

-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.

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-Publisher SEC

-Name Regulation S-X (SX)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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-SubTopic 10

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-Paragraph 12

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+ Details

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- Definition

Interest rate stated in the contractual debt agreement.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Details

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number APB14-1

-Paragraph 31

-Subparagraph b

-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.

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-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 21

-Paragraph 16, 20

-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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

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-Paragraph 1A

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Balance Type:	debit
Period Type:	instant

- Definition

The effective interest rate at the end of the reporting period.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

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-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

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-Subparagraph (SX 210.5-02.19(b),22(b))

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB

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-Number 210

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-Paragraph 16

-Subparagraph a(1)

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