Long Term Liabilities (Details Textuals) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Senior Credit Facility Details [Abstract]
Revolving Bank Loan Comitment Value	$ 1,000,000,000
Max Revolving Bank Loan Comitment Value	1,250,000,000
Letters Of Credit Availability	250,000,000
Credit Facility Lender Consent Requirement	50.00%
Bank indebtedness	460,000,000	277,000,000
Available borrowing capacity	540,000,000
Debt Instrument Interest Rate Terms Prime	125
Debt Instrument Interest Rate Terms Libor	225
Senior Notes [Abstract]
Other Long Term Notes Payable	$ 450,000,000
Interest Rate	5.75%
Debt Instrument Call Feature	On and after December 15, 2015, the Company may redeem all or, from time to time, a part of the Notes at the following prices expressed as a percentage of principal amount of the Notes: (2015 – 102.875%; 2016 – 101.438%; and 2017 and thereafter – 100.000%).

Percentage requirement from consenting banks for commitment extensions under the revolving credit facility.

No definition available.

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- Definition

Description of the interest rate as being variable and identification of the LIBOR index as the rate on which the interest is based and the number of points or percentage added to that index or rate to set the rate.

+ References

No definition available.

+ Details

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- Definition

Description of the interest rate as being variable and identification of the Prime index as the rate on which the interest is based and the number of points or percentage added to that index or rate to set the rate.

+ References

No definition available.

+ Details

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- Definition

Fixed interest rate - senior notes

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

The total amount available to be issued as letters of credit under the Company's bank credit facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum aggregate commitment available under the current revolving credit facility.

+ References

No definition available.

+ Details

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- Definition

Initial loan commitment for revolving credit facility.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Details

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- Details

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- Definition

Description of a feature that permits the issuer of the debt to repay or convert it before the stated maturity date (early retirement date). The description may include such items as the call price, the period that the issuer can call the debt, including the earliest call date, and other significant terms of the call feature, which may include the debt holders' ability to convert the debt to equity if the call option is exercised and contingent events that trigger the issuer's ability to call the debt.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 4: 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(a)(5))

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

+ Details

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- Definition

Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

+ 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(b))

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Subparagraph b

-Article 5

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Balance Type:	credit
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- Definition

Including the current and noncurrent portions, the carrying value as of the balance sheet date of notes payable to banks, excluding mortgage notes, initially due beyond one year or beyond the operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

+ Details

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- Definition

Carrying value of the noncurrent portion of notes payable which were initially due after one year or beyond the normal operating cycle, if longer, and which are not otherwise defined in the taxonomy.

+ 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)

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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