Leases and Commitments - Narrative (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Leased Assets [Line Items]
Lease expense	$ 23,568,000us-gaap_LeaseAndRentalExpense	$ 24,726,000us-gaap_LeaseAndRentalExpense	$ 24,205,000us-gaap_LeaseAndRentalExpense
Buildings and equipment capitalized under capital leases	12,169,000us-gaap_CapitalLeasedAssetsGross	13,435,000us-gaap_CapitalLeasedAssetsGross
Accumulated amortization in connection with capital leases	$ 4,993,000	$ 6,942,000
Minimum
Operating Leased Assets [Line Items]
Lease term	1 year 0 months 0 days
Maximum
Operating Leased Assets [Line Items]
Lease term	20 years 0 months 0 days

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45014-112735

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 2)

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

+ Details

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Details

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