Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Operating leases
Remaining 2013	$ 35,044
2014	129,549
2015	119,376
2016	106,774
2017	95,970
Thereafter	510,749
Total	997,462
Minimum sublease rentals to be received in the future under non-cancelable subleases	155,715
Minimum rental commitments, real estate leases and equipment leases	904,059
Minimum rental commitments, service and maintenance agreements	93,403
Commitment to invest in limited partnerships
Commitment to invest in limited partnerships	35,971
Loss Contingency, Information about Litigation Matters
Litigation settlement accrual	$ 4,000

Represents the entity's commitment to invest in limited partnerships

No definition available.

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- Definition

Represents the portion of future contractually required payments on operating leases related to real estate and equipment leases.

+ References

No definition available.

+ Details

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- Definition

Represents the portion of future contractually required payments on operating leases related to service and maintenance agreements.

+ References

No definition available.

+ Details

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- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.25)

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

+ Details

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- Details

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph b(i)

-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 Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-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 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

+ Details

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- Definition

Contractually required future rental payments receivable on noncancelable subleasing arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph b(ii)

-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.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount of required minimum rental payments maturing after the fifth rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the fifth rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the forth rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the third rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the second rolling twelve months following the latest balance sheet presented for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Definition

Amount of required minimum rental payments maturing in the remainder of the fiscal year following the latest fiscal year ended for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

+ Details

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- Details

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