Lease Agreements - Future minimum rental payments uder operating anc capital leases (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Capital leases minimum payments for 2013	$ 415
Capital leases minimum payments for 2014	396
Capital leases minimum payments for 2015	392
Capital leases minimum payments for 2016	197
Capital leases minimum payments for 2017	0
Capital leases minimum payments for later years	0
Capital leases minimum payments total	1,400
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating leases minimum payments for 2013	14,401
Operating leases minimum payments for 2014	11,375
Operating leases minimum payments for 2015	10,091
Operating leases minimum payments for 2016	8,702
Operating leases minimum payments for 2017	8,007
Operating leases minimum payments for later years	24,130
Operating leases minimum payments total	$ 76,706

Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments maturing in the next fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the forth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing in the second fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments maturing after the fifth fiscal year following the latest fiscal year for capital leases.

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

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

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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)

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-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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