Long-term Debt Long Term Debt (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Long-term debt and capital lease obligations	$ 1,615,449us-gaap_DebtAndCapitalLeaseObligations	$ 1,624,712us-gaap_DebtAndCapitalLeaseObligations
Less: current portion	67,398	84,366
Long-term debt, less current portion	1,548,051	1,540,346
Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term debt	1,584,044	1,583,798
Debt instrument, interest rate, stated percentage	1.92%	2.13%
TEUs - Amortizing note [Member]
Debt Instrument [Line Items]
Long-term debt	11,184	21,878
Debt instrument, interest rate, stated percentage		4.50%
Coupon rate	5.00%	5.00%
Other debt [Member]
Debt Instrument [Line Items]
Long-term debt and capital lease obligations	$ 20,221	$ 19,036
Maximum [Member] \| Other debt [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	10.00%	10.00%

Coupon rate

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- Definition

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ 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

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13,16)

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- Definition

Contractual interest rate for funds borrowed, under the 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

-Article 5

Reference 2: 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)(1))

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

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 7

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Number 210

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- Definition

Amount of long-term debt and capital lease obligation due after 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 Regulation S-X (SX)

-Number 210

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

-Section H

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

+ References

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